Foundation Code compliance and Best Practices By Michael Coello

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1 Foundation Code compliance and Best Practices By Michael Coello

2 Background Graduated cum laude in 1992 with a Bachelor of Science degree in finance from University of Wisconsin - Parkside Started poured concrete foundation division at Coello & Associates, Inc. in 1993 Member of MBA arbitration commitee since 1997 and co-chairman of UDC commitee from 2005 to Certified Concrete technician of the American Concrete Institute. Appointed to the Wisconsin Uniform Dwelling code council for one and two family dwellings in November of Help maintain the MBA Masonry and Concrete standard.

3 Overview Code compliance consists of the Uniform Dwelling code and by adopting standards also includes ACI 318 and 530. Three primary functions of a full depth residential foundation. Soils Concrete and Steel

4 American Concrete Institute Instruction manual for concrete and masonry. ACI 318 (Engineering guidelines and minimum requirements for concrete) ACI 530 (Engineering guidelines and minimum requirements for masonry) ACI 332 (Guidelines for residential construction)

5 Three jobs of full depth residential foundations Support the live and dead loads from above. Resist backfill soil pressures. Keep water out.

6 Point loads and lintels

7 Soil loads

8 Types of soil and weight Granular soils deposited by the Glaciers. Typically a stone sand mix. Weighs from 30 to 60 pcf depending on the clay content. As you get to Madison it is 100% sand. Will provide very high bearing capacities with great draining characteristics. Compressive or expansive soils that are prevalent within the Great Lakes water shed basin. Mostly clay and when wet will weigh up to 120 pcf. When in contact with moisture it becomes a very unstable soil with very low bearing capacity and usually does not drain well. Noncompacted Fill or organic soils. No bearing capacity and when wet is extremely heavy and drains very poorly.

9 Soil type tables

10 Cohesive Soils Vs Granular Soils

11 Fill soils

12 Too heavy for the wall design A competitor s wall in New Berlin. Very heavy wet clay blew in wall.

13 Prescriptive design Tables from ACI

14 Keeping the foundation dry is in the details! Need to control the surface water. Grade should be down from the top of the foundation wall no less than 8 inches. Proper pitch away from home should be ¼ for ten feet or 2% minimum. Drainage plain details looked after at the interface between the foundation and the rim joist/ skirt. Water table height of all bodies of water need to factored in. Retention pond outlets and spill ways need to be factored into footing height. No less than 18 above water table. Topographical features of the lot must be factored into the foundation design. In a lot of municipalities no thought is put into where the water will go especially on large lots. Proper foundation drainage system. One of the issues of older foundations is that the drain tile system plugs or has improper pitch to the sump system. Even if you have a great drainage system it may plug with silt. Poured concrete walls only leak through ties, cracks or honey comb.

15 Ties

16 Critical factors with foundation systems as it pertains to moisture intrusion Exterior and interior drainage system. Standard 3 drain tile and form-a-drain systems. Temperature steel Good consolidation techniques Low water to cement ratio with a dense concrete mix design to reduce shrinkage

17 Perforated drain tile Positives are that it is inexpensive, can conform to most any shape, and is readily accessible at most hardware stores and supply houses. Negative is that it is not all installed at one time making it easily corruptible and it is hard to keep at a set height. Therefore valleys can become an issue and cause a negative pitch from the sump area.

18 FORM-A-DRAIN System for enhanced performance Patented 3-in-1 foundation solution forms footings, provides integrated drainage, & can be easily adapted to vent radon if needed

19 Standard layout. Code change now requires 15 feet between crossovers.

20 Can Easily Adjust For Drainage And Cannot Be Corrupted

21 How to deal with silty soils.

22 Soils may be fine at the time of the footing but unforeseen circumstances may affect the system later.

23 Proper consolidation during the pour will reduce a significant amount of call backs. Right mix poured at the right slump when compacted properly will yield a very dense, strong, water impervious structure. If crews are pouring with little or no effort the mix may be too viscous unless proper admixtures were added. Vibrators and puddling must be utilized to compact all elements of the concrete.

24 Improper consolidation

25 Control Joints with Waterstop For Water Tightness! Forms create a V in the wall to control where cracking occurs Metal Waterstop is placed in wall at the control joint to prevent water from entering the basement

26 Temperature steel vs. Structural steel

27 Basement wall not design as retaining wall. Sill plate connection restrains the top of the foundation wall. Size and spacing of anchors need to be determined based on unbalanced fill height ACQ lumber treating requires double dipped galvanized or zinc plated fasteners

28 Jump steel reinforcement

29 Window steel reinforcement

30 Different types of deformed steel Grade 60 steel is required in all structural reinforcing applications.

31 Durable concrete Key concrete terms are slump and strength tests

32 One extra gallon of water per yard will: Will increase the slump approx. 1 Cut the compressive strength by as much as 200 psi Waste ¼ bag of cement Increase shrinkage potential 10% Decrease freeze/thaw resistance by 20% Decrease resistance to deicing attack There are several other ways to get work ability / flow ability without adding water.

33 Minimum for strength and slumps

34 Big Or Small Basements Are More Apt To Be Finished Than Ever Before This makes the need for a dry and comfortable basement greater than ever!