Foundationwaterproofing.org's preferred method of waterproofing foundations is second to none. While many foundation companies propose solutions that encompass some of the steps that are covered here, most do not implement the 7 step process that makes this the best available solution for damp or wet basements.
To make and keep your basement dry, look for the following 7 Steps:
A combination of machine and hand digging allows access your foundation to begin the waterproofing process without any risk of damage to the foundation. Your contractor must excavate all the way to the footing to examine the existing drainage and the condition of the foundation wall and footing. Once the excavation is complete, power-wash the foundation to remove all loose materials and examine the foundation for damage.
Depending on the condition of the foundation, this step may vary. If there is any substantial damage to the foundation it will have to be repaired. After any damage is repaired, the contractor should apply 2 coats of parging. The parging provides damp-proofing and provides a foundation for the additional waterproofing layers.
In addition to parging the foundation, ask the contractor to apply a bevel of concrete at the joint where the foundation meets the footing. This helps to seal up one of the most vulnerable parts of the foundation. This seam is often the source of water getting into basements.
Blueskin is a rubberized asphalt membrane laminated to a Polyethylene film. This combination provides a durable, waterproof barrier that is tough and flexible and can stretch to continue providing protection even if new cracks develop after the membrane has been applied.
After the parging layers have dried, a primer is rolled on and then the Blueskin applied over the primer. The priming layer provides the perfect surface for the Blueskin to adhere to and provides a small amount of damp-proofing on its own. Remember, the Blueskin is providing waterproofing not just damp-proofing.
After the Blueskin, the foundation should be wrapped in Platon Membrane which provides the first defense against water and provides physical protection to the Blueskin membrane. Platon Membrane is a tough, dimpled, 24-mil high-density polyethylene wrap that seals out water. The dimples provide an air gap behind the Platon so that any water that might get behind the membrane can drain down and won't be trapped between the Platon and the Blueskin.
The next 2 steps in ensuring a dry basement are perhaps the most important: proper drainage and grading. It essential that when water flows down the Blueskin and Platon membranes that there is a system in place to carry the water away from the foundation. The age of your home will often determine the drainage solution that is available for your foundation. You may be connected to the city storm drain, a French drain on your property or to a sump pit in your basement. However, regardless of drainage solution, your contractor shouldl lay a new bed of gravel at the footing, install new window wells and drains if required, install new weeping tile and connect it to the drainage. The weeping tile has a “sock” that covers it to help filter out silt so that the pipe does not clog as quickly over time. Finally the new weeping tile is covered with clear gravel so that water can drain easily through it.
After the waterproofing steps are completed, the excavation around the foundation is backfilled and graded so that there is sufficient slope around the house to encourage water to run away from the foundation. Keeping water from getting to the foundation is the first line of defence in keeping a dry basement.
By executing these 7 steps, you will have the best solution for a dry basement. Waterproofing your foundation is a significant undertaking and investment and you want to be confident that the work is done right and that the result will be a dry basement.
Comments
I need your advise on this. I just undergone to get my basement watter proofing.
The team didn't apply the Platon Membrane and New weeping tile.
They said the weeping tile is still good and if to change that they need to change the whole house weeping tile.
They just applied "BlueSkin waterproof membrane" and Backfilled.
I am concern if that is enough.
Please advise.
Prm
( horizontal plan) with a blue
skin membrane?
Thanks,
sophie
Please help.
Thanks.
Raj
We have problem with our TDC duct which is going out side the building to the roof. We tried to seal the joints with Tarp liquid . but its still leaking. the water is getting in from some where throw any small hole. We are looking for hundred pro cent solution . Any Suggestion ..? Can blue skin apply on the tarp liquid ..? its dry but its little sticky.
Please help.
Thanks.
Raj
Can you just use blueskin and backfill against that or do you have to have the black dimple plastic against that also?
I believe the manufacturer considers that acceptable. I like the extra protection of the dimple membrane over top of the blueskin because the dimple is tougher and will stand up to more abuse during backfilling. However, if you're backfilling with sand or something else that is clean and free from anything that might tear or damage the blueskin, then you're probably ok without the dimple membrane. Personally, I don't want to have to dig up my foundation more than once so for the little extra cost for the dimple, I add the extra protection.
Tony
The top strip of the Delta should have overlapped the bottom to shed the water obviously but if the blue-skin is properly installed, it should be enough to keep the water out. I think I would do a risk analysis. What happens if there is a leak? Is it an expensive finished basement that will be damaged? If you know that the blue-skin is installed properly, I think I'd leave it as is and see if there are any water problems inside. If you want to be a little more confident, I think I'd only excavate enough to replace the top row of Delta. Full excavation seems like overkill to me.
The only thing to do is to re-excavate the foundation wall down to the level of the joint and install a new upper sheet correctly.
Tony
Kerri
I've never encountered that before. I would suggest checking the manufacturer's instructions. You might want to contact them directly.
In theory I would think that if the foundation was dry and clean, the blueskin would adhere but I don't know enough about wood foundations to know if there are other issues that might come up.
Two part question. negative slopes towards the building.
Building constructed on concrete slab.
1) is membrane /blue skin necessary ?
2) Is it advisable to install weeping tile and French drain.?
Soil is sandy under slab and generally sandy loam surrounding building.
thanks..
I think with the negative slope toward your building, I would want to bring in someone with experience to look at it and assess the situation on-site. It's going to depend to some degree on how much area is collecting water and how steep the slope is and whether there are other contributing factors that will result in large volumes of water coming toward your building.
It sounds like it's time to rely on some local expertise.
Is this of concern?
Thanks,
Bryce
According to the makers of Blueskin, it seals around nail penetrations. http://henry.com/airandvapor/nonpermeable/blueskinWB
Also, the platon membrane is usually only nailed quite high up, so unless your water table is really high, the water won't be where the nails are.
I'm not familiar with that product but from what I can see, it does sound very similar.
I haven't tried applying blueskin over tar so I can't be sure what will happen. Blueskin is incredibly sticky so I would expect that if the tar is thoroughly cleaned, removing any dirt and dust and then primed properly, it would stick. I'd suggest you check their Web site for more technical details or contact one of their sales reps which can be found at: http://www.na.graceconstruction.com/template.cfm?page=/contact_sbm/sbm_contact.html&did=11&sid=33
Good luck with the project
-My foundation wall is block for about 2' down from the surface, then slab, then poured foundation wall, then footing.(techni cally slab on grade, but ground level is a little higher on this wall) The block has old tar on it down to the poured foundation wall, and down to the footing in one section. Can membrane stick over this old tar? The suggested parge coat would not stick well over the old tar, correct? Removing all the tar would not be possible...
Love your website, great info here.
Thank you.
You're doing a full blueskin around your foundation so it sounds like you're off to a good start. Make sure it's fully adhered everywhere before backfilling. I'd talk to some local experts to get their thoughts as well. A lot of building inspectors are able to offer constructive advice on what they've seen in the area. If you plan for the sump pump but don't put it in, you can add it later without too much trouble (just don't plan on finishing that part of the basement right away and make sure that you have weeping tile installed so that it's in place if you do decide to add one later.
Definitely get more opinions from local experts and good luck with the project.
Draining the sump onto your sidewalk isn't ideal. You don't say what georgraphic region you're in but in Ottawa, your sump can still be pumping when it's below zero outside which means you'll be coating your sidewalk in ice. The water is relatively warm coming out of the ground but once it's on the surface, it will freeze on a cold day. In general, it's better to pump it out onto a grass or gravel area well away from the house where some of it can soak into the ground and the rest can run off onto the street.
Legally, I'm not sure I like the idea of having one sump in one house. What are the legal repercussions if the sump in your basement fails. It also means all of the water is in your basement if it fails so you get all the damage.
Some cities allow you to hook your sump to the sewage line but many do not.
Putting in just the weeping tiles with gravel may help to distribute the water around the foundation which may help it to disappate faster and therefore not leak into the house but if it doesn't lead somewhere, you may not be solving the problem.
If you're going to excavate, the weeping tile is a small amount of the cost so definitely do this.
Hope that helps.
Hello,
I am living in a townhome (one of 6) and one of my neighbours has leaking in her basement which apparently comes from my side. The foundation never had weeping tiles (we know this for a fact). It was suggested that we waterproof and add weeping tiles (o.k. so far) and that one of the units put in a sump pump to which some of us can connect (some would but some will not).
My question: the sump pump would have to drain onto the sidewalk then out to the street. Is this o.k. because I read somewhere that Mike Holmes does not think so? This is highly stressful if only because the money is adding up and if some of us connect to this sump pump we will legally need to set up an agreement . Can we just have the weeping tiles with the gravel all around and leave it at that? Do we need weeping tiles at all especially since some units will never agree to link to my tile on the right? Next year we must look at the back of the unit with the same issues and problems. Thank you for any advice. Ann
You've got a pretty serious waterproofing challenge on your hands. If I were you, I'd call some local experts to see what they would recommend.
First, you want to make sure the ground around your house is graded away from the house so that water isn't being channeled back to the house and make sure you have eavestrough all the way around and your downspouts are away from the house. Then, take a look at the pumps you were using. There are huge differences in how much water each of them can pump. Higher volume pumps tend to cost more but will do a better job in a high volume situation.
The "inside wall trench" method is what Atlantic Basements does. You may want to check that out but I wouldn't say that that is the only solution. If the walls are waterproofed with blueskin, and there is weeping tile to carry the water quickly to the sump pump(s), and you have high volume pumps to keep up with the flow, that should be enough to stop water coming up through the floor.
It will happen again. I will spend the money on water proofing the outside walls of the foundation but what can I do about the floor of the basement? In a response to another question you mentioned a trench around the perimeter of the floor that directs the water into the sump...but if our sump pumps were overwhelmed would that even help?
I'm on a slope and my brick house is built on sandstone,
To water proof between the brick and footing could I cement a spoon drain then black jack then black plastic then a French drain?
Cheers
Rob
One question, am I seeing there that the dimple plastic is running over the clear gravel and weepers?
If not would you put filter fabric over the 3/4 clear gravel
Before you backfill?
Thanks don
I recently hired someone to waterproof a basement wall. I was not able to be there when the work was done. He says he went all the way below where the footer and the wall meet with the membrane. I am still experiencing a leak between the footer and the wall, and there is a considerable leak about 18" up from the floor and 18" in from one corner where there was a hole in the foundation. This hole now literally squirts water out onto the floor. The contractor says it is water getting behind the membrane. Should this even be possible? I would think if he did what he says he did that would not be possible. He claims his membrane covers the entire wall and footer and is sloped out away from the basement wall at the bottom.
Thanks
Wrapping the blueskin all the way down and over the footing where the bevel would have been will probably also accomplish much the same thing as the bevel.
The blueskin membrane is supposed to give you the waterproof layer that is required where there's a high water table. You may still need a sump pump to keep the water from coming up through the floor of the basement and if you do, make sure you put in at least two pumps and one pump with a battery back-up.
Adding the Platon over top of the blueskin adds a physical protective layer which is not be necessary but is one more layer of insurance. Platon alone does not work against a high water table. Since it is not sealed to the foundation, it can not keep water out if the water table rises above the footing. The water level will rise behind the platon and it's not doing anything then.
The footing area may be the most vulnerable because the walls are poured after the footings are dry so there isn't a continuous connection between the wall and the footing but by putting blueskin on the whole foundation you have a continuous waterproof membrane from top to bottom. No place for the water to get through or behind the membrane.
same height?
2" higher?
lower?
I'm not sure what you mean by foundation coating. If you mean parging, then yes it should be parged.
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