Crack Control Joints

[aroncone]

I am looking for field experiences of HI's in reporting on crack control joints with homes 10 plus years.

This item was called out in the report.
Background Info,
Home Inspection included a 2001 autumn built home with concrete poured foundation walls with a crack control joint, inverted V, crack opening less than 1/16, with no visible moisture prevention above grade. Vertical joint is 30' from rear corners of the home (left and right sides). Foundation walls wrapped with a delta membrane, type of waterproofing unknown. It is unknown if adjacent walls to the crack control joint are keyed or what type of moisture prevention was utilized below grade. Strength of concrete is unknown unless tested.

Your thoughts and input regarding your experiences with crack control joints is greatly appreciated.

If home builders would adopt ISO/QS quality controls in their assemblies a lot of guess work would be eliminated.

Anyone ever tested for concrete strength, any recommended labs?

Thanks!

[Douglas Cossar]

Interesting comments however, we do a limited visual inspection of readily accessible systems and components of the home. We can't inspect things we can't see.

Was there evidence of water intrusion? That's really all the customer is interested in.

Concrete strength testing is way beyond the SOP.

Just keep it simple and understandable for the customer.

Just my $.02

Hope this helps

[Marcel R. Cyr]

Originally Posted by aroncone

I am looking for field experiences of HI's in reporting on crack control joints with homes 10 plus years.

This item was called out in the report.
Background Info,
Home Inspection included a 2001 autumn built home with concrete poured foundation walls with a crack control joint, inverted V, crack opening less than 1/16, with no visible moisture prevention above grade. Vertical joint is 30' from rear corners of the home (left and right sides). Foundation walls wrapped with a delta membrane, type of waterproofing unknown. It is unknown if adjacent walls to the crack control joint are keyed or what type of moisture prevention was utilized below grade. Strength of concrete is unknown unless tested.

Your thoughts and input regarding your experiences with crack control joints is greatly appreciated.

If home builders would adopt ISO/QS quality controls in their assemblies a lot of guess work would be eliminated.

Anyone ever tested for concrete strength, any recommended labs?

Thanks!

Hi. Aurelio;

Not quite sure exactly what you are looking for, but will give it a try.

First, we need to understand the difference between control joints, expansion joints, and construction joints.

A typical control joint for foundations is usually spaced at 30' intervals around the perimeter of the wall and look like this.



The exterior of the wall joint formed, would typically get filled with an elastermic compound to look like a band-aid joint prior to waterproofing the exterior.

Wall Expansion Joints

Wall expansion joints should be designed to accommodate the anticipated movement. Historical evidence indicates that wall movements below grade are generally nominal and the effective work of the seal is limited. For treatment of leaks providing amplified external drainage media similar to that required on the exterior wall is highly effective. Special emphasis is placed on evacuating the water at the wall base to avoid water build-up in the back fill or drainage system.

Waterstops

Waterstops should be utilized at construction joints in below grade walls, footings and other elements where a waterproof system is required. These systems prevent the passage of water across these cold-joints. Waterstops are manufactured products available in a wide range of configurations and sizes. Common materials include polyvinyl chloride (PVC), neoprene, and thermoplastic rubber.



This is what is used for testing existing concrete

For In-Place Testing of Normal and High-Performance Concrete

Measures the compressive strength of concrete accurately and effectively, on site in the field.
The Windsor HP Probe™ system rapidly and accurately determines the concrete compressive strength of a structure by driving a probe into the concrete with a known amount of force. Improved and enhanced over thirty years, this modern system is capable of measuring concrete with a maximum compressive strength of 17,000 PSI (110MPA). It has been ruggedized for use in the construction environment, yet refined to provide the user with a simpler system to operate. An electronic measuring unit has been added to help ensure proper test results which can be recorded for later review or uploading to a personal computer.

Any concrete testing firms in your area could be found in the yellow pages, I would expect.

Let me know if you were looking for something other than this, I may be able to help.

Marcel

[Brian A. MacNeish]

Originally Posted by aroncone

I am looking for field experiences of HI's in reporting on crack control joints with homes 10 plus years.

This item was called out in the report.
Background Info,
Home Inspection included a 2001 autumn built home with concrete poured foundation walls with a crack control joint, inverted V, crack opening less than 1/16, with no visible moisture prevention above grade. Vertical joint is 30' from rear corners of the home (left and right sides). Foundation walls wrapped with a delta membrane, type of waterproofing unknown. It is unknown if adjacent walls to the crack control joint are keyed or what type of moisture prevention was utilized below grade. Strength of concrete is unknown unless tested.

Your thoughts and input regarding your experiences with crack control joints is greatly appreciated.

If any contractor is using crack control techniques, you've got someone who is way ahead of the pack. They've been recommended to residential builders as a better building practice since the 1980's but I have yet to ONE!!!

If home builders would adopt ISO/QS quality controls in their assemblies a lot of guess work would be eliminated.

Anyone ever tested for concrete strength, any recommended labs?

My summer high school and university jobs were with the dept of Highways. I did thousands of tests of aggregates (Proctors) and cracked a lot of cylinders at 7 and 28 days of wet curing. Never have donea test on home yet.

Had one house where a normal shrinkage crack had occurred with water leakage unsuing. I got called from a RELO company from Dallas, Tx (this house was in Moncton, NB) to go inspect the house. The owner/vendor had already called engineers in about the crack......I figure they took him for a ride:
(1) It was a normal foundation shrinkage crack in a subdivision of generally better homes. This home was 7 years old.
(2) they did core tests of the wall and the floor slab
(3) They recommended that the drain tiles be replaced ($10,000)
(4) yes, they finally recommended that the crack be sealed from the exterior.

My opinion: It probably cost the owner $12,000+ overall. I feel they should have paid to patch the crack firstly to see if this was the only problem ......cost $400-600. If this solved the problem, move on!!!

There will rarely be need to test the concrete strength in housing as we're overbuilding them now with 8 and 10" thick walls in average housing without very high point loads or exterior wall finishes.

Thanks!

Note: I've built (1987) a full 2 storey home on 2X8 preservative treated wood studs on wet clay/silt/sand soils along a lake. By removing the heavy concrete, we removed the danger of settling since in this house the concrete would be the overall heaviest load.