Abstract. 2. Cold Pitched Roofs
|
|
- Blaise Hawkins
- 7 years ago
- Views:
Transcription
1 Heat and moisture transport between houses and cold lofts - a combination of convection and diffusion Emannuel Essah and Chris Sanders Glasgow Caledonian University Abstract About 80% of domestic pitched roofs in the UK today have insulation on a horizontal ceiling with an accessible, cold loft space above; this leads to a risk of condensation on the underside of the roof covering. Simple calculations suggest that heat flow is equally split between conduction and air flow through gaps in the ceiling, while about 80% of moisture flow goes by air movement. Therefore condensation risks in this system cannot be assessed without taking account of air movement. The paper describes typical air flow routes, methods of measuring airflows through the ceiling and a risk assessment model based on simple empirical performance rules, that is being used for sensitivity analysis. A preliminary CFD model of the air flows through pitched roofs that is being developed with FLUENT, and which will be used to refine the risk assessment model, is described. 1. Introduction Most (70 80%) houses and some larger buildings such as hospitals or schools, in the UK have cold pitched roofs, with insulation on a horizontal ceiling with an accessible, cold loft space above. The ceiling contains gaps, such as around loft hatches and service penetrations, which provide routes for air to flow from the occupied space into the loft. There are also more complex air flow routes, for example through wall cavities and behind lining systems 1. Some of the heat and moisture generated within the house leaves via the loft, passing through the ceiling by a combination of conduction/diffusion and air motion. This movement contributes significantly to heat loss from the house and leads to a risk of condensation within the loft. All the four sets of building regulations in force in the British Isles require that the performance of building structures or the health of the occupants are not adversely affected by surface or interstitial condensation. The requirements are implemented by reference to the relevant parts of BS5250:2002 2, the British Standard Code of Practice for the Control of Condensation in Buildings, which in turn refers to the calculation procedures in BS EN ISO 13788: However, structures with airflows through cracks and cavities are specifically excluded from the scope of this Glaser based standard. As airflows dominate the movement of moisture into cold pitched roofs, assessments of condensation risk using this procedure are not valid. A new procedure, taking account of air flows, is being developed. 2. Cold Pitched Roofs Cold pitched roofs are made up of a number of elements which affect their thermal performance and the risk of condensation occurring within the structure. Typically these elements are: Mineral wool insulation, which offers little resistance to air movement and moisture diffusion, is placed on a horizontal plasterboard ceiling. The ceiling is commonly penetrated by an access hatch and services allowing air to pass into the cold loft; there are also often more complex routes for air movement via, e.g. wall cavities. The accessible loft space above, used for storage and may contain water tanks, etc. 1
2 A tiling underlay, traditionally an impermeable bitumen felt, but now being replaced with lighter, vapour permeable membranes, laid with overlaps through which air can flow. The external weatherproof roof covering, a discontinuous sheet which, allows relatively free movement of external air into the batten space between the tiles/slates and underlay. With this construction, there is a risk that water vapour generated within the house will penetrate the ceiling, by diffusion and air movement, and condense on the underside of the underlay. The accepted solution has been to introduce ventilation into the loft space. More recently, however, vapour permeable underlays have been used as an alternative to ventilation of the loft. 3. Moisture damage Traditionally it has been assumed that high air relative humidities in the loft cause the hygroscopic timbers to absorb water vapour, until the moisture content becomes high enough to promote rot that may result in structural failure. Loft relative humidity has therefore been felt to be the important parameter controlling risk. However, while seasonal wetting and drying cycles occur, there is little evidence that they cause a problem. Formation of condensate on the underlay, which is cooled overnight by longwave loss from the adjacent tiles is more significant event. In many cases any condensation will be a fine dew that will form overnight and evaporate rapidly during the day. There is reason to believe that this occurs on many nights, even in the summer. However if conditions are such that the accumulation of condensate is very severe or prolonged (Figure 1), the condensate can run or drip onto adjacent timbers, causing the timbers to rot, or the ceiling insulation, reducing the effectiveness of the insulation while it is wet. Staining or mould growth, and in extreme cases, physical deterioration of the roof elements can result (Figure 2). Figure 1: Condensation droplets on an undertiling membrane Figure 2: Wood rotting fungi growing on roof timbers 4. Measurement of ceiling leakage Fan pressurisation equipment is commonly used to measure the overall air leakage characteristics of houses. Further information can be gained on leakage through individual components by sealing them off and repeating the test. In principle, information on the leakage though a ceiling could be gained by sealing all the other leakage paths before carrying out a pressurisation test. This is however totally impractical in any real building, because of the many complex paths. 2
3 The only alternative is to use tracer gas methods, which are complex, time consuming, require expensive equipment and cannot generally be carried out in occupied buildings. Two separate tracer gases are used; one is injected into the dwelling space (regarded as one volume, with all the internal doors open) and the other into the loft. The concentrations in both areas are diluted with fresh air from outside and some tracer is carried from the dwelling space into the loft, giving the change in concentration shown in Figure 3. Because of wind flows over the roof and temperature differences through the ceiling, in winter there will be little or no flow from the loft downwards Concentration : ppm House Tracer 1 Loft Tracer 1 Loft Tracer Time : Hours Figure 3 Tracer gas concentrations measured in a house and its loft The airflow from the house to the loft can then be calculated from the information on the tracer gas concentrations. The air flows dwelling space of a house, its roof and outside are shown, in Figure 4 Figure 4 - Air flows between a house, its loft and outside If the airflows are as shown in Figure 4, a general equation is obtained for determining the concentration of tracer in the loft at time t, as: 3
4 βht βrt βrt ( e e ) + C (o) e X hr 1 Cr (t) = Ch (o) r Vr βr βh Xho + X hr Xoh where β h = = is the ventilation rate, derived from the decay of tracer gas in the Vh Vh house 4. X ro β r = is the ventilation rate in the roof that is derived from injecting tracer into the roof alone. Vr All the X values are in m 3 /h, V= volume m 3 ; C = tracer concentration ppm; and the subscripts h, r and o refer to the house, roof and outside respectively. Equation 1 can be represented as C r (t) = AX hr + B Where βht Ch (o)(e e A = V (β β ) r r h βrt ) and B = C (o)e r βrt The value of X hr which gives the best fit to the observed concentration in the roof is found by least squares and is given by: X ( C (t) A) ( AB) r hr = 2 A The sums are taken over each measurement period Empirical rules A series of measurements of the ventilation rates of houses and their lofts and air movement through the ceiling, using tracer gases, were made in about eighty houses in Scotland and England, in the 1970s and 80s [1]. These enabled the following broad rules to be developed: Loft ventilation: When the loft is unsealed, but with no eaves or ridge ventilators, the loft ventilation rate in air changes per hour (ach), was about equal to the wind speed in m/s. When there is a 10mm slot in the eaves on both sides of the house, the loft ventilation rate in ach, was about equal to 2 times the wind speed in m/s. When there is a 10mm slot in the eaves on both sides of the house and a 5mm ridge ventilator, the loft ventilation rate in ach, was about equal to 2.5 times the wind speed in m/s. Air flows through the ceiling: With similar ventilation openings on the upwind and down wind sides of a house, about 20% of the air entering the occupied rooms of a house, leaves via gaps in the ceiling into the loft. About 20% of the air entering a loft comes through the ceiling from below. 4
5 One area of practical interest that has not been resolved is the effect of ridge ventilators. It is agreed that if there are 10mm openings in the eaves, the addition of 5mm ridge ventilators will increase the loft ventilation rate significantly, perhaps excessively so. What is more uncertain is the addition of ridge ventilators, when there is limited or no ventilation at the eaves. It is agreed that this will increase the loft ventilation, but there is speculation that the negative pressures at the ridge will suck more humid air through the ceiling, increasing the risk of condensation. There are no measured or modelled data to confirm or reject this possibility. If air leakage through the ceiling is reduced, this will reduce the whole house ventilation rate, but not by the same amount, because of readjustment of flows in the space below the ceiling. The BRE single zone model, BREVENT, which takes account of wind and stack driven ventilation through planned openings and infiltration through residual leakage paths, was used to investigate this effect. The results for a typical detached house are shown in Figure 5. This shows the airflow through the ceiling and the total air flow through the house as a function of the ceiling leakage area. As the ceiling is tightened up, the ceiling flow falls by 130 m 3 /hr, while the whole house flow falls by only 54 m 3 /hr. As a broad rule therefore, it has been assumed that reducing the airflow through the ceiling has half the reduction on the flow through the house Air flow : m 3 /hr Through Ceiling House Total ,000 10,000 15,000 20,000 25,000 30,000 35,000 40,000 45,000 50,000 Ceiling leakge area: mm 2 Figure 5 Whole house air leakage and ceiling leakage as ceiling leakage area varied 6. Heat and moisture transport into the loft Table 1 shows the moisture and heat transfer between a typical three bedroomed house and its loft, by conduction or diffusion and by air movement, assuming a typical unsealed ceiling and 10mm ventilation slots in both eaves. Conduction and air movement contribute about equally to the heat transport when 200mm of mineral wool insulation is laid on the ceiling. However 75% of moisture transport is by air movement, with only about 25% diffusing through the ceiling. 5
6 Table 1 Transfer of heat and water vapour from a typical house into its loft by conduction or diffusion through the insulation and by air movement through gaps in the ceiling. Conduction or Diffusion Air movement Heat Transfer: W Moisture Transfer: g/h ROOFCOND model In principle a model could be developed in which the airflows through all the leakage routes were calculated explicitly and used in combination with the conduction/diffusion flows of heat and moisture to calculate the condensation risk in any specific roof. In practice the information on flow paths, leakage areas, etc. necessary to achieve this in any particular building is not available. A different approach based on the empirical rules developed from measurements has been used to develop a model that can be used for sensitivity analysis. Four processes affect conditions within a roof and the risk of moisture damage. Heat and water vapour are generated within a building by the normal activities of the occupants, raising the internal temperature and vapour pressure above that outside. Temperature and vapour pressure differences drive heat and water vapour through the materials by conduction and diffusion respectively. Air flows from the house to loft and through the loft to the outside carry heat and water vapour. Solar radiation raises the temperature of the roof covering and underlay above the air temperature during the day and night sky radiation lowers the roof temperatures below the air temperature overnight. The model that has been developed, ROOFCOND 5, carries out a dynamic heat and moisture balance of the loft and batten space, with the following boundary conditions: External - Years of hourly values of temperature, humidity, wind speed, global, direct and diffuse solar radiation from appropriate sites. Internal - a constant internal temperature of 20 C and internal vapour load derived from the climate classes in Annex A of EN ISO 13788:2001. And the following parameters of the roof: The dimensions of the roof and loft. It is assumed the roof is a simple duo pitch with gable ends and the ridge running east to west, there are therefore north and south facing slopes. The vapour resistance and thermal conductivity of the ceiling, insulation, underlay and roof covering; The air leakage characteristics of the ceiling, any eaves and ridge ventilators in the loft and batten space, the overlaps in the underlay and the gaps between the tiles or slates. 6
7 Hourly values of the underlay and roof covering temperatures are calculated, taking account of solar gain and long wave loss. The temperature and humidity in the loft and batten space are calculated and used to calculate the rate of condensation or evaporation on the underlay and roof covering. The main issue that is not taken into account in the model is thermal and vapour storage in the materials, i.e. moisture and heat flows are assumed to be instantaneous. Given the importance of airflows in this type of structure it is felt to be a small approximation, however work is in progress to refine the model to take storage into account. 8. Performance indicators In principle, several indices of roof performance could be derived, including mean relative humidity in the loft and batten space, time that the humidity exceeds a certain amount etc. However in practice it has been found that the most sensitive parameter is the peak accumulated condensate on the north facing underlay. As an example of type of output from the programme, Figure 6 shows the accumulation of condensate in two lofts over a year, starting at the beginning of July. In roof A condensation is not a problem, however small amounts (< 10 g/m 2 ) of condensate accumulate on many nights in autumn and spring, with a peak accumulation of 12.8 g/m 2 in November. Condensation is a major problem in Roof B. There are frequent small accumulations overnight in late summer and autumn, but then a steady accumulation from early November until mid April. In practice, a peak accumulation of over 400gm/m 2 would not occur as there would be significant running and dripping of condensate over the whole winter in this roof. Accumulated Condensate g/m Accumulated Condensate g/m JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN 0 JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN Roof A Well sealed ceiling, unventilated loft, low resistance underlay Roof B Unsealed ceiling, restricted loft ventilation, high resistance underlay Figure 6 Calculated condensate accumulation in two lofts 9. Sensitivity analysis The airflows in this model, the dominant transport processes are based on based on very broad empirical rules, and therefore the model will not be suitable as prediction tool for assessing the performance of specific roofs. Its main use is envisaged to be for sensitivity analysis. There will also always be uncertainty as to the appropriate external climate conditions to use and the exact performance of any model. One method dealing with these uncertainties is to define a base case 7
8 roof type that experience has shown to work well, and relate the peak accumulated condensate in any other roof, calculated with the same model under the same climate, to that occurring in the base case roof. The base case that that has been adopted in the UK is a roof with 10 mm ventilation slots in both eaves, an impermeable bitumen felt underlay, an unsealed ceiling with 200 mm of mineral wool, and a roof covering of slates which have accumulated dirt and moss, limiting the air flow through them. This is the most common roof type in the UK, and provided that the moisture production in the house below the ceiling is not excessive, has not given any problems for many years. The peak condensate accumulation in this roof in London is 42 g/m 2. To illustrate the effect of varying some important roof parameters, Figure 7 shows the relative condensation peak as the loft eaves gap is reduced in four roofs, all of which have 200 mm on the ceiling and a roof covering of clean interlocking tiles. Restricting the loft ventilation increases the condensate peak in all cases, however there are benefits in changing from a high resistance (HR) underlay, with vapour resistance S d = 40, to a low resistance (LR) underlay, with S d = 0.05, and in reducing the leakage through the ceiling by 70% by improving the sealing of that ceiling. Figure 8 shows the effect of increasing the thickness on mineral wool insulation from nothing up to 400 mm in a range of roof types. As might be expected because insulation on the ceiling will make the roof above colder, the condensation rate increases significantly with increasing insulation thickness. The picture is slightly more complex because the added insulation thickness will also increase the vapour resistance of the ceiling, reducing the condensation risk. This effect can been seen as the condensate peak falls slightly when the first 25mm of insulation is added to the uninsulated, well sealed ceiling. 4 Relative condensate peak HR underlay, unsealed ceiling HR underlay, well sealed ceiling LR underlay, unsealed ceiling LR underlay, well sealed ceiling Eaves ventilation gap : mm Figure 7: Relative condensate peak as a function of loft eaves gap 8
9 3 2.5 HR underlay, 10 mm eaves, unsealed ceiling HR underlay, 3 mm eaves, unsealed ceiling LR underlay, 3 mm eaves, unsealed ceiling HR underlay, 3 mm eaves, well sealed ceiling Relative condensate peak Insulation thickness : mm Figure 8: Relative condensation peak as a function of ceiling insulation thickness 10. CFD Simulation So that the model can be revised and made more representative of a wider range of roof types, a programme of tracer gas measurements and CFD simulation is in progress. These will be described in more detail in a paper to be presented at the Montreal Building physics conference in September In order to address these issues a 2D model has been developed as a preliminary study. In this model, the standard turbulence k-epsilon (k-ε) was used with a transient unsteady state solver. Representative pressure values, obtained from a detailed wind tunnel experiment are imposed at the eaves, while the inlet pressure in the lower room was taken from measured data. It is assumed that the wind is coming from the left, as illustrated in Figure 13, and the roof surface was assumed to be impermeable, with heat flux values (representing solar radiation) imposed on the roof. Roof Heat Flux (Wm -2 ) Upward eaves Pressure Inlet (Pa) Downward eaves Pressure Outlet (Pa) Lower room(source) Pressure Inlet( Pa) Ridge Pressure Outlet(Pa)/ Wall Results Modelling was performed in several stages with different eaves, ridge and irradiance controls scenarios. These are summarised in Table 2 9
10 Table 2 Scenarios for various modelling techniques Scenario Eaves Ridge Opened Ridge Closed Roof Gap Pressure Outlet(Pa) Irradiance(W/m 2 ) Irradiance(W/m 2 ) N/A 100 3mm 2 N/A N/A mm N/A The negative value at the ridge is because pressure at the ridge is considered to have a suction effect. Initial results from the air speed derived from the model are shown in Figures 9-12 m/s Figure 9 - Calculated air speeds - 3mm eaves gap no ridge vent m/s Figure 10 - Calculated air speeds - 10mm eaves gap no ridge vent 10
11 m/s Figure 11 - Calculated air speeds 3 mm eaves gap with ridge vent m/s Figure 12 - Calculated air speeds 10 mm eaves gap with ridge ventilator 11. Conclusions This paper has discussed the factors that affect the risk of condensation in cold pitched roofs, the most common domestic roof type in the UK, which heat and especially moisture flows are dominated by airflows through the fabric. Tracer gas measurements have allowed the development of empirical airflow relationships that have been used to develop a sensitivity analysis tool, which is being used to identify the important factors in roof performance. A CFD model of airflows is being developed to refine the performance of the model and extend its applicability. 11
12 References [1] C.H Sanders et al: Airtightness of ceilings - energy loss and condensation risk, BRE Information Paper, IP 4/ [2] British Standards, BS 5250:2002. Code of Practice for control of condensation in buildings. BSI (2002) [3] BS EN ISO Hygrothermal performance of building components and building elements Internal surface temperature to avoid critical surface humidity and interstitial condensation Calculation methods [4] C.H.Sanders. Air movement in houses: a new approach. Building Research and practice, (1982) [5] C.H. Sanders and J. Haig. Heat, air and moisture transport through cold pitched roofs: CIB W40, Glasgow meeting (2004) 1-5. [6] E. Essah et al, Air flows between houses and their roofs, to be presented at the Montreal Building Physics Conderence September
BUILDING CONTROL GUIDANCE SHEET USE OF BREATHABLE ROOFING FELTS.
Building Control Charnwood Borough Council Southfield Road Loughborough LE11 2TN BUILDING CONTROL GUIDANCE SHEET USE OF BREATHABLE ROOFING FELTS. Last updated 16/11/2010 Page 1 of 6 PURPOSE: This Guidance
More informationEnergy Company Obligation (ECO): Technical Monitoring Questions
Energy Company Obligation (ECO) Technical Monitoring Questions v1 30/05/2013 Energy Company Obligation (ECO): Technical Monitoring Questions Under ECO suppliers are required to instruct suitably qualified
More informationMoisture Content in Insulated Basement Walls
Moisture Content in Insulated Basement Walls Peter Blom,PhD, SINTEF Building and Infrastructure; peter.blom@sintef.no, www.sintef.no/byggforsk Sverre B. Holøs M.Sc. SINTEF Building and Infrastructure;
More informationMulti-layer Insulation Blanket for Roofs
Multilayer Insulation Blanket for Roofs Thermal Insulation in a 40mm thin, flexible, multilayer membrane Meets requirements of L1A, L1B 2010 In accordance with BR443 NHBC Acceptance Pitched & Flat roof
More informationCode of practice for control of condensation in buildings
BRITISH STANDARD BS 0:00 Incorporating Amendment No. 1 Code of practice for control of condensation in buildings ICS 91.10.99 Committees responsible for this British Standard The preparation of this British
More informationEnergy Efficiency in Buildings
Energy Efficiency in Buildings Supplemental Guide to SANS 10400-XA & SANS 204 V. 3.0 Registered to: The Drawing Studio Image: digitalart / FreeDigitalPhotos.net Report Date: 26 August 2014 Practice Name:
More informationRoofers Guide to Underslating Membranes
Roofers Guide to Underslating Membranes IKO is a worldwide enterprise, with more than 3000 employees, and manufacturing plants in Canada, the United States, United Kingdom, Belgium, Holland, France and
More informationROOFS, SNOW AND ICE DAMS
ROOFS, SNOW AND ICE DAMS The Problem Ice dams are a common roof performance problem in cold climate buildings. Simply put, they are ridges of ice and icicles caused by melt water from further up the roof
More informationRochdale Building Control Guide. Approved Document C. Site preparation and resistance to contaminants and moisture
Rochdale Building Control Guide Approved Document C Site preparation and resistance to contaminants and moisture Dampness is often misdiagnosed within buildings, the approved document deals with prevention
More informationPreventing Ice Dams on Roofs
Preventing Ice Dams on Roofs Facility Manager November/December 2005 When a roof leaks, facility managers inevitably receive complaints from building occupants. If it is winter, ice dams are often the
More informationMechanical and Natural Ventilation
BBSE3006: Air Conditioning and Refrigeration II http://www.hku.hk/bse/bbse3006/ Mechanical and Natural Ventilation Dr. Sam C. M. Hui Department of Mechanical Engineering The University of Hong Kong E-mail:
More informationGuide to the safe installation of downlighters in dwellings
Guide to the safe installation of downlighters in dwellings Technical guidance for designers and installers 01 Guide to the safe installation of downlighters in dwellings Technical guidance for designers
More informationCONDENSATION IN REFRIDGERATED BUILDINGS
CONDENSATION IN REFRIDGERATED BUILDINGS By: Steve Salisbury Nov. 10, 2010 (revised Nov. 14, 2013) Introduction The following discussion reviews the basic causes of condensation in refrigerated buildings
More informationIncluding. Rubershield-Pro. Breather Membrane
Including RubershieldPro Breather Membrane 2 Ruberoid produces a wide range of underslating membranes, primarily to be installed below tiles, slates or metal roofing providing a secondary barrier against
More informationCondensation. Some Causes, Some Advice
Condensation Some Causes, Some Advice The Problem Condensation on windows and in conservatories, and the damage it does to paintwork, curtains, wall coverings and window fittings, are problems frequently
More informationAsphalt Shingle Application Requirements
Alberta Allied Roofing Association Asphalt Shingle Application Requirements Section 1 Roof Decks 1.1 General Asphalt Shingles are not permitted to be installed directly over rigid insulation. When Asphalt
More informationAdvice to consumer Reference 50.1 May 2013. Condensation. Some causes, some advice.
Advice to consumer Reference 50.1 May 2013 Condensation Some causes, some advice. 03 Contents The issue 04 What is condensation 06 The factors governing condensation 09 How double or triple glazing helps
More informationCERTIFICATE NAME OF PRODUCT MANUFACTURER PRODUCT DESCRIPTION CERTIFICATION PROCEDURE. No VTT C-6044-10 Date of issue 11.10.2010, Updated July 1, 2011
CERTIFICATE NAME OF PRODUCT No VTT C-6044-10 Date of issue 11.10.2010, Updated July 1, 2011 H-CONTROL REFLEX+ reflective insulating vapour control layer for roof and wall applications MANUFACTURER ACTIS
More informationROOFERS CHOICE BREATHER MEMBRANES FOR USE IN COLD NON-VENTILATED ROOFS
Mercury Building Products Ltd 114 Eckington Road Coal Aston Dronfield Sheffield S18 3AY Tel: 01246 292816 Fax: 01246 292867 e-mail: sales@vaprfree.co.uk danny@vaprfree.co.uk website: www.mercurybuildingproducts.com
More informationMolds and mildew are fungi that grow
Appendix C: Moisture, Mold and Mildew Molds and mildew are fungi that grow on the surfaces of objects, within pores, and in deteriorated materials. They can cause discoloration and odor problems, deteriorate
More informationNational Building Code of Canada 2010
National Building Code of Canada 2010 Emergency Change Issued by the Canadian Commission on Building and Fire Codes The table that follows lists two emergency changes that apply to the National Building
More informationSTAYFLEX CORROSION CONTROL AND THERMAL INSULATION SYSTEM
STAYFLEX CORROSION CONTROL AND THERMAL INSULATION SYSTEM Installed in Pre-engineered Steel Buildings Provides Lowest Cost Construction Method for CORROSIVE AND WET Environments PREFERRED SOLUTIONS, INC.
More informationEFA PSBP. Natural Ventilation Strategy. Introduction. 1.1 Relevant legislation. 1.1.1 The Building Regulations 2010
EFA PSBP Natural Ventilation Strategy Introduction The Baseline Designs Project will provide scheme design details for a number of Primary and Secondary School Exemplars. For the purposes of setting a
More informationPart 3 Ancillary technologies. Chapter 3.2. Mechanical ventilation with heat recovery
Part 3 Ancillary technologies Chapter CONTENTS SCOPE Clause Page DESIGN Design standards D1 1 Statutory requirements D2 1 System design D3 1 Building integration D4 2 Noise D5 2 Access and controls D6
More informationIntroduction & Principles Issued in support of Junction Details, Parts 1 to 5
Accredited Construction Details (Scotland) 2010 For the limitation of thermal bridging and air infiltration in low and medium rise domestic buildings Introduction & Principles Issued in support of Junction
More informationANSI/ASHRAE Standard 140-2004 Building Thermal Envelope and Fabric Load Tests
ANSI/ASHRAE Standard 140-2004 Building Thermal Envelope and Fabric Load Tests DesignBuilder Version 1.2.0 (incorporating EnergyPlus version 1.3.0) - June 2006 1.0 Purpose The ANSI/ASHRAE Standard 140-2004
More informationHome inspectors are not mold inspectors, however they do inspect for defects that
CONDENSATION IN THE WALLS Home inspectors are not mold inspectors, however they do inspect for defects that can result in mold. Mold grows in wet or damp environments. Defects that result in a wet or damp
More informationAND MEMBRANES ROOFING UNDERLAYS. www.fakro.com
AND MEMBRANES 010 ROOFING UNDERLAYS 1 HO DOES YOUR ROOF BREATHe? MEMBRANES THE WAY to A WARM AND DRY ROOF HO HO HO HO HO HO WATERTIGHTNESS The FAKRO Company offers a wide range of membranes and underlays
More informationCFD SIMULATION OF SDHW STORAGE TANK WITH AND WITHOUT HEATER
International Journal of Advancements in Research & Technology, Volume 1, Issue2, July-2012 1 CFD SIMULATION OF SDHW STORAGE TANK WITH AND WITHOUT HEATER ABSTRACT (1) Mr. Mainak Bhaumik M.E. (Thermal Engg.)
More informationCO2 Emissions. Indirect CO 2. Emissions Electricity and Heat Production 25 % Direct Emissions AFOLU 24 % Energy 1,4% Buildings 6,4 % Industry 11 %
CO2 Emissions Direct Emissions AFOLU 24 % Buildings 6,4 % Transport 14 % 49 Gt CO2 eq (2010) Indirect CO 2 Emissions Electricity and Heat Production 25 % Energy 1,4% Industry 11 % Transport 0,3 % Industry
More informationSANS 1 0 1 7 7-9. www.spunchem.com FIRE PERFORMANCE SANS 428 ENERGY SAVER REFLECTIVE TIASA A MEMBER OF 2009/366 2009/367 2009/369 2008/341
REFLECTIVE ENERGY SAVER FIRE PERFORMANCE SANS 428 SANS 1 0 1 7 7-9 SANS 10177-10 SANS 10177-11 www.spunchem.com A MEMBER OF TIASA Thermal Insulation Association of Southern Africa 2009/66 2009/67 2009/69
More informationSika Membran System For Sealing and Waterproofing Construction Gaps in Building Façades
Construction Sika For Sealing and Waterproofing Construction Gaps in Building Façades Waterproof and Airtight Flexible Seal Controlled Vapour Diffusion Bonds to any Building Substrate Prevents Interstitial
More informationConservatory Roof Structural Information Guide
Conservatory Roof Structural Information Guide Effective from ugust 8 Useful Information This guide displays data on the permissible roof member spans and for different roof loadings; it should be used
More informationAIR CONDITIONING EFFICIENCY F8 Energy eco-efficiency opportunities in Queensland Foundries
AIR CONDITIONING EFFICIENCY F8 Energy eco-efficiency opportunities in Queensland Foundries Hot tips and cool ideas to save energy and money! Air conditioning units or systems are often used by foundries
More informationPROVIDING PROTECTION IN CONSTRUCTION Technical guide: roofs. www.tyvek.co.uk www.construction.tyvek.com
PROVIDING PROTECTION IN CONSTRUCTION Technical guide: roofs www.tyvek.co.uk www.construction.tyvek.com DuPont TM membranes Providing protection Contents Page Introduction............................................................................................................................
More informationCase Studies: Infrared Heating in Industrial Applications
Case Studies: Infrared Heating in Industrial Applications Chao Chen, Puget Sound Energy ABSTRACT Puget Sound Energy (PSE) is a utility which serves more than one million electric customers and over 700,000
More informationEco Pelmet Modelling and Assessment. CFD Based Study. Report Number 610.14351-R1D1. 13 January 2015
EcoPelmet Pty Ltd c/- Geoff Hesford Engineering 45 Market Street FREMANTLE WA 6160 Version: Page 2 PREPARED BY: ABN 29 001 584 612 2 Lincoln Street Lane Cove NSW 2066 Australia (PO Box 176 Lane Cove NSW
More information*Trademark of The Dow Chemical Company A business unit of The Dow Chemical Company and its subsidiaries Copyright 2003 The Dow Chemical Company.
Dow Chemical is a Registered Provider with The American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members.
More informationFrost Damage of Roof Tiles in Relatively Warm Areas in Japan
Frost Damage of Roof Tiles in Relatively Warm Areas in Japan Influence of Surface Finish on Water Penetration Chiemi IBA Hokkaido Research Organization, Japan Shuichi HOKOI Kyoto University, Japan INTRODUCTION
More informationEnergy efficient home design
Energy efficient home design GUIDELINES How an energy efficient home can help you live in comfort and save money An energy efficient home is designed to provide shade and allow cooling breezes to enter
More informationMONARPERM 600, MONARPERM PLUS AND MONARPERM TOP (COLD VENTILATED AND WARM NON-VENTILATED)
Icopal Limited Barton Dock Road Stretford Manchester M32 0YL Tel: 0161 865 4444 Fax: 0161 866 9859 e-mail: info.uk@icopal.com website: www.icopal.com APPROVAL INSPECTION TESTING CERTIFICATION TECHNICAL
More informationRain Penetration Tests on Manthorpe Mini Castellated Vent Tile with 15" x 9" Format Roof Tiles. Prepared for: Ben Hales
Rain Penetration Tests on Manthorpe Mini Castellated Vent Tile with 15" x 9" Format Roof Tiles Prepared for: Ben Hales Manthorpe Building Products Ltd. 24 th June 2014 Report number 295-318 1 Rain Penetration
More information2014 British Columbia Building Code Changes
District of Houston 250-845-2238 2014 British Columbia Building Code Changes A District of Houston interpretation of the 2014 Building Code Changes for 9.36 & 9.32 The following changes reflect the most
More informationIntroduction. 1. Heat Transfer. In Townsville s climate it is essential to choose building materials that perform well in our local conditions.
In Townsville s climate it is essential to choose building materials that perform well in our local conditions. Choosing the correct materials and insulation will improve the overall thermal performance
More informationContents. APA Construction Details. Full fill cavity walls 2-13. Partial fill cavity walls 14-25. Solid externally insulated walls 26-37
Contents Pages Full fill cavity walls 2-13 Partial fill cavity walls 14-25 Solid externally insulated walls 26-37 Appendix (BRE confirmation of Ψ and y-values) 38-40 Page 1 of 40 APA Construction Details
More informationAdaptive strategies for office spaces in the UK climate
International Conference Passive and Low Energy Cooling 631 Adaptive strategies for office spaces in the UK climate I. Gallou Environment & Energy Studies Programme, Architectural Association Graduate
More informationCITY OF WHITE BEAR LAKE BUILDING INSPECTION DEPARTMENT 4701 Highway 61 White Bear Lake, MN 55110 Fax: 651-429-8503. Re-Roofing: Asphalt Shingles
CITY OF WHITE BEAR LAKE BUILDING INSPECTION DEPARTMENT 4701 Highway 61 White Bear Lake, MN 55110 Fax: 651-429-8503 Re-Roofing: Asphalt Shingles This is a summary of the standard requirements based on the
More informationSubtropical Cities September 2006. Design for Energy Efficiency in Commercial Buildings in Queensland
Subtropical Cities September 2006 Design for Energy Efficiency in Commercial Buildings in Queensland Contents Typical Building Constraints & Requirements Understanding Energy Consumption in Buildings HVAC
More informationCHAPTER 3. BUILDING THERMAL LOAD ESTIMATION
CHAPTER 3. BUILDING THERMAL LOAD ESTIMATION 3.1 Purpose of Thermal Load Estimation 3.2 Heating Load versus Cooling Load 3.3 Critical Conditions for Design 3.4 Manual versus Computer Calculations 3.5 Heating
More informationTHE REDLAND GUIDE TO BS 5534
THE REDLAND GUIDE TO BS 5534 HELPING YOUR COMPANY TO GET ONE STEP AHEAD www.redland.co.uk Enforcement is via authorities such as the National House Building Council (NHBC) and Local Authority Building
More informationAT&T Global Network Client for Windows Product Support Matrix January 29, 2015
AT&T Global Network Client for Windows Product Support Matrix January 29, 2015 Product Support Matrix Following is the Product Support Matrix for the AT&T Global Network Client. See the AT&T Global Network
More informationAPPENDIX C - Florida Energy Code Standard Reference Design Auto-Generation Tests
REM/Rate v15 Review 9/22/14 Purpose This document includes the results of limited testing and verification of the REM/Rate v15.0 software submitted as a simulation tool for demonstrating compliance with
More informationDispelling the Solar Myth - Evacuated Tube versus Flat Plate Panels. W illiam Comerford Sales Manager Ireland Kingspan Renewables Ltd.
Dispelling the Solar Myth - Evacuated Tube versus Flat Plate Panels W illiam Comerford Sales Manager Ireland Kingspan Renewables Ltd. 1 The Kingspan Group Energy independent buildings for a sustainable
More informationRESNET National Rater Test Study Guide Outline
RESNET National Rater Test Study Guide Outline The RESNET national home energy rating standard spells out a listing of the knowledge base and skills set for Home Energy Ratings. Trainers and Rating Quality
More informationTHE IMPACT OF ENERGY EFFICIENT REFURBISHMENT ON THE AIRTIGHTNESS IN ENGLISH DWELLINGS
THE IMPACT OF ENERGY EFFICIENT REFURBISHMENT ON THE AIRTIGHTNESS IN ENGLISH DWELLINGS Sung H. Hong 1, Ian Ridley 2, Tadj Oreszczyn 3, The Warm Front Study Group 4 1, 2, 3 Bartlett School of Graduate Studies,
More informationCFD AND MULTI-ZONE MODELLING OF FOG FORMATION RISK IN A NATURALLY VENTILATED INDUSTRIAL BUILDING
2000 Elsevier Science Ltd. All rights reserved., Air Distribution in Rooms, (ROOMVENT 2000) Editor: H.B. Awbi 767 CFD AND MULTI-ZONE MODELLING OF FOG FORMATION RISK IN A NATURALLY VENTILATED INDUSTRIAL
More informationCIBSE Weather Files 2016 release: Technical Briefing and Testing
CIBSE Weather Files 2016 release: Technical Briefing and Testing Authors: Dane Virk and Matt Eames Test Reference Years The TRY weather file represents a typical year and is used to determine average energy
More informationINSULATED PITCHED ROOFING
DOW CONSTRUCTION PRODUCTS (a division of the Dow Chemical Company Ltd) INSULATED PITCHED ROOFING Welcome to this RIBA approved CPD self tutorial. First some information about the Dow Chemical Company itself:
More informationRESIDENTIAL ROOFING & RE-ROOFING, ROOF VENTILATION AND ROOF SHEATHING REQUIREMENTS MICHIGAN RESIDENTIAL CODE 2000
RESIDENTIAL ROOFING & RE-ROOFING, ROOF VENTILATION AND ROOF SHEATHING REQUIREMENTS MICHIGAN RESIDENTIAL CODE 2000 SECTION R905 REQUIREMENTS FOR ROOF COVERINGS R905.1 Roof covering application. Roof coverings
More informationFACTORS AFFECTING ENERGY CONSUMPTION OF BUILDINGS
FACTORS AFFECTING ENERGY CONSUMPTION OF BUILDINGS 1 Ralf Lindberg, Professor Minna Korpi, M.Sc. Juha Vinha, Dr.Tech. June 11, 2008 Department of Civil Engineering, Tampere University of Technology 2 BACKGROUND
More informationAN APPLICATION MANUAL FOR BUILDING ENERGY AND ENVIRONMENTAL MODELLING
AN APPLICATION MANUAL FOR BUILDING ENERGY AND ENVIRONMENTAL MODELLING D. Bartholomew *, J. Hand #, S. Irving &, K. Lomas %, L. McElroy # F. Parand $, D. Robinson $ and P. Strachan # * DBA, # University
More informationVENTILATIVE COOLING EBC ANNEX 62 PER HEISELBERG DEPARTMENT OF CIVIL ENGINEERING
VENTILATIVE COOLING EBC ANNEX 62 PER HEISELBERG DEFINITION OF VENTILATIVE COOLING VENTILATIVE COOLING IS APPLICATION (DISTRIBUTION IN TIME AND SPACE) OF VENTILATION AIR FLOW TO REDUCE COOLING LOADS IN
More informationCAN DEMAND CONTROLLED VENTILATION REPLACE SPACE HEATING IN OFFICE BUILDINGS WITH LOW HEATING DEMAND?
Topic B3: Control of indoor environment CAN DEMAND CONTROLLED VENTILATION REPLACE SPACE HEATING IN OFFICE BUILDINGS WITH LOW HEATING DEMAND? Axel CABLE 1,*, Mads MYSEN 1,2, Kari THUNSHELLE 1 1 SINTEF,
More informationModule 3.7. Thermal bridging
Module 3.7 Thermal bridging Learning Outcomes On successful completion of this module learners will be able to - Describe construction details which influence thermal bridging. 2 Introduction to thermal
More informationSignificance of Glazing Thermal Conductivity for MAC Indirect Emissions and EV Battery Performance
Significance of Glazing Thermal Conductivity for MAC Indirect Emissions and EV Battery Performance Steve Gasworth and Triloka Tankala SABIC Innovative Plastics sgasworth@exatec.biz steven.gasworth@sabic.com
More informationDamp Causes and Solutions
Damp Causes and Solutions The subject of damp in buildings invites much comment and speculation. The issue is often misunderstood and proposed solutions are often expensive, damaging, and usually affect
More informationThe impact of climate change on the environmental design of buildings
Technical Note Summary Buildings are designed for a specific climate yet they often have a lifetime of 100 years. Climate change may require a building to operate over a range of climatic conditions as
More informationThe Pleasance, Edinburgh
Refurbishment Case Study 5 DRAFT The Pleasance, Edinburgh Insulation of coom ceiling, attic space & lightwell 2 nd edition The views expressed in commissioned case studies are those of the authors and
More informationCrawl space heat and moisture behaviour
Crawl space heat and moisture behaviour Miimu Airaksinen, Dr., Technical Research Centre of Finland, VTT miimu.airaksinen@vtt.fi, www.vtt.fi KEYWORDS: crawl space, moisture, evaporation from ground, ground
More informationPROFILED METAL ROOFING DESIGN GUIDE
MCRMA Technical Paper No. 6 CI/SfB (23) Nh2 JUNE 2004 PROFILED METAL ROOFING DESIGN GUIDE THE METAL CLADDING & ROOFING MANUFACTURERS ASSOCIATION LIMITED Contents Page 1.0 Typical construction and assemblies
More informationProblem Statement In order to satisfy production and storage requirements, small and medium-scale industrial
Problem Statement In order to satisfy production and storage requirements, small and medium-scale industrial facilities commonly occupy spaces with ceilings ranging between twenty and thirty feet in height.
More informationDealing with damp and mould growth
Dealing with damp and mould growth Dampness affects many homes in Britain. There are three main causes of dampness. This guide aims to help you to work out what may be the cause of the damp and how you
More informationOpening the Bonnet. Prof Darren Woolf WYSINWYG 1
Opening the Bonnet Prof Darren Woolf WYSINWYG 1 WYSINWYG What You See Is NOT What You Get: Looking inside the Pandora s Box Prof Darren Woolf WYSINWYG 2 WYSIWYG implies a user interface that allows the
More informationBEST 2 WB 3 4 SIX WAYS FOR CONDENSATION IN BUILDINGS. Wagdy Anis, FAIA, LEED ap*
BEST 2 WB 3 4 SIX WAYS FOR CONDENSATION IN BUILDINGS Wagdy Anis, FAIA, LEED ap* Abstract: Six of the ways condensation can occur on cold surfaces in buildings are discussed here. They are: 1. Air Leakage,
More informationTsawwassen BC Arena Before & After installation of the Low-E ceiling
LOW EMISSIVITY CEILINGS Emissivity- Describes the ability of a certain material to radiate heat rather then absorb it. Materials that radiate 100% have an (EM) of 1.0, while materials that radiate no heat
More informationHousing Fact Sheets. Energy Saving Window Treatments
Housing Fact Sheets Energy Saving Window Treatments Windows are a major source of heat loss but they are necessary for light, ventilation, and view. In a typical single family home, about 20% of the heat
More informationBituminous Sheet Flat Roofs: Their repair and maintenance
Bituminous Sheet Flat Roofs: Their repair and maintenance Flat roof covered in sheets of bituminous felt Introduction Whilst flat roofs are often regarded as inferior to their pitched counterparts and
More informationresearch highlight Highly Energy Efficient Building Envelope Retrofits for Houses
research highlight June 2012 Technical Series 12-103 Highly Energy Efficient Building Envelope Retrofits for Houses introduction In Canada approximately 30% of all energy is consumed in buildings, with
More informationDealing with damp, condensation and mould growth in your home. www.homesforharingey.org
Dealing with damp, condensation and mould growth in your home www.homesforharingey.org Condensation can cause dampness and mould growth in your home. This looks unpleasant and can increase the risk of
More informationWestern Red Cedar Shingles Product Guide
Western Red Cedar Shingles Product Guide Western Red Cedar Shingles & Shakes from John Brash are a truly renewable and sustainable roofing and cladding material; with one of the lowest carbon footprints
More informationCOMPARISON OF FIXED & VARIABLE RATES (25 YEARS) CHARTERED BANK ADMINISTERED INTEREST RATES - PRIME BUSINESS*
COMPARISON OF FIXED & VARIABLE RATES (25 YEARS) 2 Fixed Rates Variable Rates FIXED RATES OF THE PAST 25 YEARS AVERAGE RESIDENTIAL MORTGAGE LENDING RATE - 5 YEAR* (Per cent) Year Jan Feb Mar Apr May Jun
More informationCOMPARISON OF FIXED & VARIABLE RATES (25 YEARS) CHARTERED BANK ADMINISTERED INTEREST RATES - PRIME BUSINESS*
COMPARISON OF FIXED & VARIABLE RATES (25 YEARS) 2 Fixed Rates Variable Rates FIXED RATES OF THE PAST 25 YEARS AVERAGE RESIDENTIAL MORTGAGE LENDING RATE - 5 YEAR* (Per cent) Year Jan Feb Mar Apr May Jun
More informationAnalysis of Energy Consumption, Rating Score, and House Size
Analysis of Energy Consumption, Rating Score, and Duncan Prahl, Registered Architect Innovation Programs Leader, Research and Development, IBACOS, Inc., Phone: + 1 412 325 1523. Fax: + 412 765 3738. E-mail:
More informationSolar air collectors for industry and larger halls S Ø. Efficient dehumidification and air heating for free...
Solar air collectors for industry and larger halls N S Ø Efficient dehumidification and air heating for free... This booklet contains information about SolarVenti Industrial air solar system. The system
More informationFire 2This Technical Bulletin has been commissioned by the UK SIP Association in
REV 1-12.12.11/TB002 Technical Bulletin Fire 2This Technical Bulletin has been commissioned by the UK SIP Association in conjunction with TRADA Technology and is intended to provide the reader with introductory
More informationA Roof Integrated Solar Heating System Without Storage
M. and W. Saman Sustainable Energy Centre University of South Australia Mawson Lakes Boulevard, Mawson Lakes, SA 5095, Australia E-mail: martin.belusko@unisa.edu.au Abstract A prototype of a roof integrated
More informationHousing Fact Sheets. Moisture Condensation at the Windows
Moisture Condensation at the Windows Housing Fact Sheets This fact sheet discusses the causes of and remedies for wintertime condensation problems that occur on windows, glass, and other glazing materials
More informationAssessing the effect of attic moisture in wood framed multi-unit row housing blocks.
Assessing the effect of attic moisture in wood framed multi-unit row housing blocks. ABSTRACT Rene R. Boucher This paper represents the results of poor moisture management and control of an extensive stock
More informationSolving Persistent Moisture Problems and Moisture Damage
B etter buildings Solving Persistent Moisture Problems and Moisture Damage Summary This three-storey, 15-unit, 1,300 square metre (13,993 sq. ft) walk-up was built in 1958. In the 1980s, the building started
More informationEnergy Efficiency and Historic Buildings. Insulating Pitched Roofs at Rafter Level
Energy Efficiency and Historic Buildings Insulating Pitched Roofs at Rafter Level Summary This guidance note provides advice on the principles, risks, materials and methods for insulating pitched roofs
More informationPerformance of low pressure mechanical ventilation concept with diffuse ceiling inlet for renovation of school classrooms
Downloaded from orbit.dtu.dk on: Jun 22, 2016 Performance of low pressure mechanical ventilation concept with diffuse ceiling inlet for renovation of school classrooms Terkildsen, Søren; Svendsen, Svend
More informationChapter 2 Basis of design and materials
Chapter 2 Basis of design and materials 2.1 Structural action It is necessary to start a design by deciding on the type and layout of structure to be used. Tentative sizes must be allocated to each structural
More informationWARMFILL CAVITY WALL INSULATION WARMFILL CAVITY WALL INSULATION FOR MASONRY CAVITY WALLS
Warmfill Limited Unit 5, Port of Larne Business Park Redlands Road Larne BT40 1AX Tel: 028 9042 8260 Fax: 028 9042 7641 e-mail: sales@warmfill.com website: www.warmfill.com APPROVAL INSPECTION TESTING
More informationMistrale. Fusion Terminal
Mistrale Fusion Terminal PUBLICATION NATURAL VENT. 1 SEPT 2015 Features - Slimline energy efficient ventilation solution - Standard and high capacity terminals provide 128 or 256 L/s capacity - Compliant
More informationBER Assessors Dwellings Technical Bulletin
BER Assessors Dwellings Technical Bulletin Issue No. 2/12 April 2012 Contents: 1. SUPPLEMENTARY ELECTRIC WATER HEATING IN SUMMER... 2 2. PITCHED ROOF U-VALUE CALCULATIONS... 8 2.1. PITCHED ROOF, INSULATED
More informationOptimum Solar Orientation: Miami, Florida
Optimum Solar Orientation: Miami, Florida The orientation of architecture in relation to the sun is likely the most significant connection that we can make to place in regards to energy efficiency. In
More informationA few good reasons to have a conservatory. The conservatory structure
Conservatory styles A few good reasons to have a conservatory The conservatory structure PLAY FAMILY TIME In essence a conservatory is like a big jigsaw with all the pieces joining together to form a finished
More informationHVAC Calculations and Duct Sizing
PDH Course M199 HVAC Calculations and Duct Sizing Gary D. Beckfeld, M.S.E., P.E. 2007 PDH Center 2410 Dakota Lakes Drive Herndon, VA 20171-2995 Phone: 703-478-6833 Fax: 703-481-9535 www.pdhcenter.com An
More informationTHERMAL STRATIFICATION IN A HOT WATER TANK ESTABLISHED BY HEAT LOSS FROM THE TANK
THERMAL STRATIFICATION IN A HOT WATER TANK ESTABLISHED BY HEAT LOSS FROM THE TANK J. Fan and S. Furbo Abstract Department of Civil Engineering, Technical University of Denmark, Brovej, Building 118, DK-28
More informationBuilding Owners Guide to a Duro-Last System!
Building Owners Guide to a Duro-Last System Table of Contents Section 1: Introduction to Duro-Last Roofing Systems Section 2: Benefits of a Duro-Last Roofing System Section 3: Comparing a Duro-Last Roof
More information