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6fthook_gw

Foundation waterproofing as much as possible & superior walls exp

6fthook
9 years ago

Hi everyone,

We are getting close to the production phase of our modular home here in Connecticut. We're currently doing extensive research on foundations and ways to be as waterproof/resistant as possible.

The building company has a site work company that they typically use and they have experience with Superior Walls and typical poured foundations. Our question in this post is two fold:

1. Do you have any exoerience with Superior Walls? Most of the reviews I've read are from installers who love the speed of installs. But since we're the future homeowners, what we care about is the strength and longterm durability and water resistance compared to typical poured foundations. Since we're getting close to winter, an advantage of Superior Walls is that install can be year round even if the ground is frozen.

2. If we go the poured concrete route, we want the basement to be as water resistant as possible. We want to go way overkill with every precaution possible to ensure no water problems. What are some options we should consider, and what things do we need to make sure the foundation company does that are required?

We are in Connecticut, the land has no wetlands, on 9.5 acres, and a gentle slope with the high side on the rear of the house. Front of the house will face north.

Thanks for any advice you can provide!

Comments (13)

  • worthy
    9 years ago

    Pre-fab foundations install faster and are more consistent than site-poured walls. Maybe a reasonable alternative in a rural location. But in the centre of a region (Toronto, Canada) of more than six million people, I've only done poured and block walls.


    Plastic membrane used in conjunction with cold joint barrier and footing barrier, weepers and gravel. Source: Cosella-Dorken

    The standard here is the required bituminous spray followed by a plastic bubble membrane such as Delta MS. Flexible weepers at the footings, as required, covered by a minimum of 6" of gravel though I prefer at least a foot.

    To be doubly sure of no problems, builders of custom projects first apply a waterproofing spray, which replaces the required bituminous dampproofing. While most builders backfill with whatever they've excavated, it's safer to use sand or other free-flowing materials. Still a lot more expensive. Frankly, I've only done it a couple of times where there were deep foundations three feet from the lot lines and there was a lot of evidence of underground streams. Cattails!

    (Caution: in cold climates, do not use 3/4 clear for free flowing fill. It will let in cold air to the footings and possibly result in severe freeze-uplift and thaw damage.)

    There are a variety of other effective waterproofing methods--such as stick-on membranes, repeated layers of fibreglass and bituminous material, rigid glass fibreboard, crystalline waterproofing sprays.


    Spray-on waterproofing provides an extra layer of waterprotection. But it is incapable of bridging large settlement cracks. Photo: Heather Joy Investments Ltd.

    In all cases where the footing is poured separately from the wall, special attention should be paid to the exterior intersection of the wall and footing. Special cove sealants should be used.

    But all conditions are local and your builder should be aware of the most appropriate measures in your area.

    This post was edited by worthy on Sat, Aug 16, 14 at 11:32

  • Annie Deighnaugh
    9 years ago

    If you have a slope, gravity is your friend. Put in a curtain drain that drains any water away from the foundation. Even though we are on gravel, and the guy installing it said it'd never see any water, we had him put a curtain drain around the foundation that is drained by gravity. Better be safe than sorry. We haven't seen any water out of it, but more important, we haven't had a wet basement. BTW, we are in CT also.

  • Annie Deighnaugh
    9 years ago

    Also, good idea to have them install the pipes to handle radon should you have an issue. We did and are glad as we did have a serious radon problem.

  • renovator8
    9 years ago

    I'm not sure why one foundation system would be better in winter. It's the excavation that needs to appen before the ground freezes too deep and that should be the same for both systems.

    Cold spray-on modified asphalt is the best waterproofing for a residence but there are many other more expensive systems. Don't use trowel-on damp proofing; it is not waterproofing.

  • manhattan42
    9 years ago

    I'm a builder and building inspector and have installed or inspected close to a thousand precast 'superior' walls foundations.

    Superior walls are stronger than block or poured concrete walls being engineered to 5000 psf or greater.

    Because of the density of the concrete, the walls are tested and listed to be installed without waterproofing or dampproofing.

    Superior walls and other similar types of precast foundation systems come pre-insulated.

    Superior walls come with built-in "studs" that make up the walls. There is no therefore no additional requirement to frame walls with Superior walls if one wishes to finish the basement.

    These studs and plates come pre-bored for ease of bolting on plates and pulling wire cables.

    Wall sections can easily be cut to add windows or door openings after installation...or bored for utility installations.

    Dollar for dollar pre-cast walls are much cheaper than conventional walls, are stronger, and afford the easiest installation.

    And while pre-cast wall systems, like block or concrete foundations walls also cannot be installed on frozen soil, Pre-cast concrete walls provide the most consistent, lowest risk, and safest winter installation possible.

    In my experience, pre-cast walls systems are superior to block and concrete without doubt.

  • bus_driver
    9 years ago

    Now have Superior Walls for 10 years-- 10 feet height. In Basements and this site I have posted and a search will find those posts. I did not add any waterproofing and have no water intrusion. But a coating on the outside might reduce humidity inside by a small amount.. Be sure to do a good job with the moisture barrier under the concrete slab. I have two dehumidifiers with automatic controls that keep my basement at 50% relative humidity.
    I definitely would use Superior Walls again.

  • dekeoboe
    9 years ago

    Our house is mostly pre-cast concrete walls. Although, due to the high psi, waterproofing may not be necessary to keep water out, it may still be required by your inspector. That's what happened to us anyway.

  • worthy
    9 years ago

    [Superior] walls are tested and listed to be installed without waterproofing or dampproofing

    Superior backs its claim that its walls don't need additional dampproofing with this ICC Evaluation.

    Dampproofing is a bare minimum Code requirement. Waterproofing is a higher standard that many builders and homeowners seek to meet.

    Here is a link that might be useful: Waterproofing vs. Dampproofing

  • mushcreek
    9 years ago

    worthy covered it well. Don't forget surface water management as well. Be sure the soil is properly graded to drain water away from the house, and have gutters installed to reduce the amount of water dumping right at the edge of the house. I would have waterproofing done even on Superior walls.

  • Brian_Knight
    9 years ago

    Excellent advice so far. Perforated PVC pipe with appropriate cleanouts, surrounded by gravel and filter fabric is very cheap insurance. I like to do them on the exterior and interior drained to daylight. The interior one is perfect for adding a vertical stack to for radon and soil gas mitigation.

  • Buoy Dave
    3 years ago

    My sister's former house had a Superior Wall basement which flooded during a period of prolonged heavy rain and ground saturation. Ground water came in through the floor flooding the entire basement. Their so-called warranty excludes "flooding" and water "seeping above and or below the Superior Walls Foundation System." To each their own but I'd rather take my chances with a poured concrete basement for my new house.

  • User
    3 years ago

    Take a look at what the good builders of the multi-million $ custom homes in your area are doing. Around here, only the tract builders are using Superior Walls.