Frequently Asked Questions

How much will it cost?

There are several variables that affect the cost of the project. Site influences such as: large trees, proximity to other buildings, accessibility by heavy equipment, type of soil, etc., can influence the cost. A general guideline is $150 to $300 per linear foot of foundation that needs to be excavated for the full 7-step process that we advocate. Make sure you get a detailed quote of what work will be included and the cost associated with the work. You also need to be prepared for the possibility of additional costs that can't be predicted until the foundation is excavated. Repairs to the foundation that cannot be identified before excavation are not usually included in the cost.

How long will it take?

Time estimates are also affected by several variables: the size of the foundation that is to be waterproofed, whether the foundation can be excavated with machines or must be dug by hand, the type of soil, and weather can all have an impact on how long the job will take. As an example, consider a 2000 square foot home that requires 100 linear feet of foundation to be excavated that can be mostly excavated by machine. There are no unexpected repairs discovered once the foundation is excavated and there are no days lost due to heavy rainfall. This job would take two weeks.

How much work will I have to do to repair the damage to my property caused by the excavation?

If your foundation requires full excavation, you can expect a lot of damage to your landscaping. A three foot trench is generally required around your foundation. The soil from the excavation is piled outside the trench and takes up a surprising amount of space. Excavation equipment like excavators also contribute to making a mess out your yard. A good contractor will endeavour to minimize the damage to your landscaping but foundation waterproofing is likely the most disruptive event your property will undergo so you should be prepared for the change. On the positive side, you can look at this as an opportunity to completely refresh the look of your property.

What will my property look like when the job is done?

The excavation and backfilling will result in restoration work being required to the ground at least 15 feet around the perimeter of the repaired foundation. Many contractors can provide you with several options to restore your landscaping from simply adding topsoil and grass seed to a full service re-landscaping with new plants, sod, and interlocking stone. Costs for additional landscaping work depends on the nature and scope of the work.

How much space do you need to get into my back yard?

The more space the contractor has, the larger the machine that can be brought in which speeds up the job. However, the smallest excavator requires a 4 foot (1.3 metre) entranceway to the yard.

What if they can't get an excavator into part of my yard?

If the company you hire can't get any excavator into your yard, they can hand dig your foundation. Hand digging will take longer than using machines and may affect the cost but gets the job done just the same. Some companies can also use a crane to drop a small excavator into your backyard depending on the placement of your house, hydro wires, etc. Don't count on that being cheap but it could get the job done faster.

What about decks and patios?

Any deck or patio that is in the way of the excavation will have to be disassembled, moved  and restored after the backfilling is complete. Some contractors will handle this work for you. The size and complexity of this work will determine the cost.

How long will it take for the back-filling to settle?

It takes many years for ground that has been excavated to completely settle again. Most of the settling will occur in the first year. You will notice significant settling and it will likely be most dramatic after heavy rainfall and during heavy spring melting. You can landscape immediately after backfilling but be prepared for some additional work as settling continues.

How much extra time does adding insulation add to the job?

The time to add insulation depends on the amount of foundation that needs insulation. By way of example, a 2000 square foot house that has 100 linear feet of foundation to be insulated would likely require an additional 2 days to insulate.

I live where it gets really cold in the Winter. Will my sump pump outflow freeze?

Generally the answer is no. The water coming out of the ground a the bottom of a basement is fairly warm all year round; even when it is -40 above ground. However, once you pump the water above ground, it becomes a different story. You have to make sure your outflow is sufficiently far away from your foundation so that it doesn't come back again and your property has to be graded so that once it leaves the pipe it keeps on flowing down to the street. The risk of freezing your outflow pipe will depend on the temperature outside and the amount of water being pumped through the pipe. If your sump only runs once an hour, then you might have a higher risk of freezing because the pipe has a lot of time to cool down between each cycle of the pump. However, if your pump cycles every few minutes, there will be so much warm water going through the pipe that you won't likely have any problems other than a small skating rink forming at the end of the pipe.

In Ottawa Canada, we installed a sump pump with an outflow pipe that came out of the house above grade, went through a couple of elbows and then had about 15 feet of 2" PVC pipe to carry the water away from the foundation. Despite a winter with many days below -20 and even colder nights, the sump outflow kept running and never came close to freezing.

So, it's impossible to say your outflow will never freeze but it shouldn't be a big concern in most areas. If you think there is still a risk, consider putting a connector on the outflow pipe inside your basement so that you can connect an outflow pipe from your sump to an internal drain in the event of an emergency.

Where do my weeping tiles drain to?

The short answer, is only the builder of your house really knows. In some houses, they don't connect to anything. They just distribute the water around the house in the hope that somewhere around the perimeter is ground that is permeable enough for the water to run away. Others connect to a french drain which is effectively a big pit somewhere in your yard that is deeper than your footing and filled with clear gravel so that it can hold a lot of water while it seeps away slowly into the ground. Newer houses often have the weeping tile connected to the street's storm drain system. Finally, some houses just have the weeping tile connected to a sump pit in the house where the water is then pumped out to the surface.

Can I connect my sump pump to the sanitary sewer in my house?

Whether or not you can connect your sump pump to the sanitary sewer depends on your city bylaws. Many cities do not allow this because their sewer systems are at capacity and having sump pumps putting large volumes of water into the system during storms overloads the system. So, connecting your sump to the sanitary sewer is not generally allowed by the building code, but I'd have to think that in an emergency, it might be your best course of action if you can't do an external outflow due to freezing or some other such problem.

How do I connect my weeping tile to the city storm drain system?

This is probably going to cost you a lot of money. If the city allows it, (many don't because it overloads their system and isn't the most environmentally friendly solution) you will likely have to pay through the nose for this service unless the city is willing to do the work for you. Typically, you will have to hire a bonded contractor because they have to cut the city street and restore it properly once the work is done. This usually costs way more than you are going to want to pay. It could cost almost as much as the rest of the foundation waterproofing work combined so this isn't usually a viable solution.

Should I expect to get a written quote for the job?

You would like to think so. A lot of contractors won't do this until you're signing the contract for the job. I suppose they think that they're sharing competitive information or maybe they're just lazy and have too much other business. The bottom line, however, is that there is going to be a lot of variability in any quote that you do get. The foundation repair company doesn't know what they're going to encounter under the ground until they start digging. They don't know the condition of your foundation until it is fully excavated and power washed. They may run into unforseen obstacles such as extraordinarily large rocks during excavation which take more time than expected to get past.

I've heard that we have a lot of clay in the soil around our house. Do I need to do anything special?

The Ottawa area has a lot of clay and this causes a lot of problems with keeping basements dry. If you're dealing with ground that has a high clay content, you may want to consider bringing in something different when it comes time to back fill your foundation. Back filling with sand will provide much better drainage than high-clay ground and won't cause as much settling as other fill.

Is installing just a Platon membrane enough?

Many companies only install Platon or a similar type of plastic membrane. Having the Blueskin isn't essential in all areas but we think that if you've gone to all the work and expense of excavating your foundation and preparing it for the platon, adding the waterproofing layer of Blueskin is only a smaller incremental expense and adds an extra layer of security to your waterproofing solution. It really takes you up from damp-proof to waterproof. That said, there are thousands of dry basements that only have a platon membrane. If your foundation has an effective weeping tile installed and the Platon membrane shielding the foundation and shedding water down to the weeping tile, you've probably got a very workable solution that will keep your basement dry.


# Guest 2014-05-16 14:13
I am talking to a contractor who uses Platon system. He doesn't recommend Blueskin saying that concrete needs to breathe to keep it from sweating that causes weeping through the walls. What can you say to that? Thanks,
# shaune 2013-09-24 22:10
Great site, thank you. It confirms the process I'm about to undertake tomorrow on my own rather than paying 4000.00. Some people tell me that its overkill to include the WP200 blueskin but if it helps from digging again anytime soon then it's all good.
# siegfried 2013-08-26 07:56
Sorry Paul,

I have not experience with wood foundations. I know they're somewhat more common in sandy areas and apparently are common in the Carleton Place area outside Ottawa but that's about all I know.
# Paul Brisson 2013-08-04 14:25
problem with drainage . foundation is treated wood frame 30 yr. old . any comments to correct.
# Paul Brisson 2013-08-04 14:23
Problem with drainage on 30 yr treated wood foundation with mildew and moisture in basement. any ideas how to correct.
# siegfried 2013-04-14 18:32
I've seen it done both ways. The last foundation I did we backfilled with sand. It compacts more easily than gravel or the soil that you took out and it still allows the water to runthrough.

I think it depends on what you took out of the hole but you'll find that if the soil has been there a long time, it will expand as its excavated. I read somewhere that virgin ground will expand as much 50% but I've never witnessed that myself. Regardless, getting all the soil back into the trench is difficult. Gravel and sand will go in and compact more easily so you'll have less settling to deal with later.
# Norm 2013-04-14 08:46
Hi , the 7 steps look great. Could you tell me if it is also better to back fill the entire hole with stone and haul away all the dirt. A friend told me that this is much better but more costly. Just wondering if its worth the extra cost.
+1 # staceybeck01 2012-10-29 15:43
I need to get basement waterproofing in Provo done but I also have family coming over for the holidays. I want to get started right away but I don't want to put them out of a place to stay if it doesn't get finished in time.
# domenic 2012-06-10 07:59
in a follow up to my previous question, i forgot to add that there is no platon installed over the Blueskin described in the question i had previous.
# Siegfried 2011-12-30 10:29
Karen, the Blueskin manufacturer recommends that the exterior wall be dry before applying the primer for the blueskin. From my own experience, if it's not very clean and dry, the primer won't dry and won't be able to do it's job.

Matt, not sure about the stone foundation, I've only worked on poured and block foundations. .
# matt 2011-12-28 19:27
What type of fastener should be used to secure the platon to a stone foundation build mostly of large rocks?
# karen 2011-12-14 14:13
should exterior wall be dry before applying membrane to it??
-1 # karen 2011-12-14 14:12
Should exterior wall be completely dry before applying membrane to it?
+1 # Leanne 2011-09-12 22:56
One of the footings of my house is above the slab, rather than below. Can you extend the blueskin to the top of the PVC pipe to prevent moisture near the footing (which, in my case, would be above the slab and would contribute to leakage)? Thanks!
# Siegfried 2011-06-07 08:34
The platon is attached to the wall with nails or screws. Nails have to be fired from a nail gun. The nails or screws can likely be put in above the blue-skin, but if they have to go through the blueskin, Bakor (maker of blueskin) says it does a good job of closing around the penetration point so it shouldn't leak.

By putting the Platon membrane on last, it adds extra protection to the SM insulation during back-fill and particularly if part of the insulation will be above the ground level where it can be damaged whether accidentally or intentionally.
# Brent Bostrom 2011-04-20 20:44
How do you attach the platon to the wall? Do the screws or nails compromise the blueskin?
If you were to use 2 inch SM would you put it between the blueskin and the platon?
Thank you