Go Back  DoItYourself.com Community Forums > Interior Improvement Center > Basements, Attics and Crawl Spaces
Reload this Page >

interior french drain with integrated vapor barrier is a good idea?

interior french drain with integrated vapor barrier is a good idea?


Old 11-15-10, 10:21 AM
Thread Starter
Join Date: Jul 2008
Location: USA
Posts: 3
Received 0 Votes on 0 Posts
interior french drain with integrated vapor barrier is a good idea?

We are evaluating companies for our basement french drain. One of the companies has an integrated vapor barrier system option. sound attractive to me. it likes this: WGBD with Gravel and Vapor Barrier | Flickr - Photo Sharing!
The vapor barrier's bottom will be burried into the french drain. On the top the vapor barrier sheet will be sealed with wall. I have a poured concrete basement. Poured in 1950. No water seen through the wall but lots of efflorescense.
What's your opinion about this?
Sponsored Links
Old 11-15-10, 12:11 PM
Group Moderator
Join Date: Oct 2004
Location: WI/MN
Posts: 19,308
Received 47 Votes on 44 Posts
I always attack water problems from the outside first, trying to move the water away with grading, gutters and downspout extensions
Old 11-15-10, 12:24 PM
Join Date: Dec 2005
Location: USA
Posts: 3,188
Received 0 Votes on 0 Posts
I had interior french drains installed quite a few years ago after several flooded basement episodes. No vapor barrier though. All they did was cut trenches along the outer perimeter of the slab and they buried drain pipes bedded in gravel that led to a sump. I added an additional sump later on.

From what I can tell in the photo the vapor barrier is intended to block/collect and water intrusion through the block wall. If that is the intent I don't know how effective it will be. In my experience most basement water (no moisture) seeps in through the seam where the wall meets the slab.

If you have water issues that are caused by periods of high water table, french drains and sump pumps are probably your best bet.
Old 11-15-10, 12:26 PM
Join Date: Mar 2005
Location: USA
Posts: 6,130
Received 0 Votes on 0 Posts
imei -

What is your concept of a "french drain"?

Is it a surface installed water collection system, a cheap trench around the perimeter interior common in the east after leakage or a true drainage system that it at the footing level (or below) that collects water and reduce the water and hydrostatic pressure on the wall before it gets into the living envelope?

Old 11-15-10, 01:05 PM
Thread Starter
Join Date: Jul 2008
Location: USA
Posts: 3
Received 0 Votes on 0 Posts
Cannot do outside basement wall waterproof but finished a project which handle sureface water (grading plus sallow french drain).

Do have water came from floor because water table is higher when record rain.

Interior french drain should be lower than footing.
Old 11-15-10, 01:21 PM
Join Date: Mar 2005
Location: USA
Posts: 6,130
Received 0 Votes on 0 Posts
Some builders put in both real interior french drains when building because it is not that expensive at that time.

Your water probably comes from the soil surrounding the house.

Apparently, this is an after "market solution" because there is a potential problem. The site information.
Old 11-16-10, 01:36 AM
Join Date: Feb 2010
Location: usa
Posts: 236
Received 0 Votes on 0 Posts
looks like 'basement systems' install'd that,,, NOTHING stops wtr from penetrating AND fnd wall IF its applied to the INTERIOR surface,,, it still penetrates - you just don't actually 'SEE' it,,, ,,, w/any system such as shown, the vapor barrier ( OR fiberglass-reinforced acrylic sheets ) are tucked down inside the exposed miradrain ( that black strip showing at the bottom ),,, that allows dripping leaking walls to drain down to the collection pipe then onto your sump.

we like to resolve water issues outside IF economically acceptable to the h/o - failing that, we install as shown on good days on not-so-good days, just not as straight

ps - NEVER below a footing w/trench bottom - it will lead to a condition known as SCOUR & could cause voids under a home's foundation
Old 11-16-10, 07:03 AM
Thread Starter
Join Date: Jul 2008
Location: USA
Posts: 3
Received 0 Votes on 0 Posts
What we want to do are (a) stop water from floor and floor-wall joint; (b) reduce moisture (walls is one of the resource of moisture I think). Interior french drain will address (a) and vapor barrier will address (b). Am I right? but I don't know how long it will last. I will be better to do those things from outside but it is not practical in our case.

What's the thickness of the footing? those salesmen told me their french drain will be a little lower than footing top to catch water. I don't want them to damage my house.
Old 11-22-10, 09:07 AM
Join Date: May 2008
Location: Connecticut
Posts: 124
Received 0 Votes on 0 Posts
That configuration shown in the picture is indeed an internal perimeter drainage system, but is definitely not a Basement Systems one, as someone here suggested.

Considering the size of the hole with the gravel, it seems to me that it is a combination of regular pipe,(my guess is either a corrugated one or a pvc pipe, perforated, buried by the wall and an inexpensive poly sheet tied to a regular baseboard system.

The square sump pit, is another given. Basement Systems dealers do not install that kind of sump pit. Their drain tiles and sump pump systems are like no other product in the market. They were specifically designed for this application and the company holds an exclusive patent on the system.

The vapor barrier they would install if requested would be also another patented product that is much thicker and multi- layered. And I say "if requested" because, when you provide adequate drainage from the outside and/or have a good drainage system inside, the water seepage through the concrete is minimized and, according to the US Department of Energy, should be allowed to evaporate into the basement somehow.

Ideally, if you plan to use your basement as storage or living space, you should run a dehumidifier to make sure the RH levels are kept at or below 55% to prevent mold, because even with adequate drainage there is always condensation happening due to differences of temperature. If you are going to finish your basement, or wants to spruce up your walls, there are much better, more energy efficient and equally affordable alternatives to control moisture and bright up the walls or to prepare them for insulation and finishing.

That kind of configuration (poly sheet tied to baseboard drain) is usually recommended for very irregular stone basement walls.

The main thing to consider in your case is: both types of water infiltration, the one through the wall-floor joint and the wall seepage (which causes the efflorescence), have one single common source: the ground around the foundation walls is over saturated with water. It gets saturated, the hydrostatic pressure pushes the water against the walls, it finds its way into the basement. Eliminate the over-saturation, eliminate the pressure, solve both problems.

The external french drain is the way builders provide adequate drainage. However, older homes were built without one, and newer homes can have one that has clogged, collapsed or was simply improperly installed, which might be your case. And because they are buried by the footing, you can't service them. And digging them out, just like happens to you, is simply not an option. It is messy, disruptive e very expensive.

That is why internal drains and sump pumps have been used for over 20 years as an alternative, and they do work very well in cases like yours.
Just make sure that the system you are buying:

1 - Offers a decent warranty on products and services. Good products are backed with Transferable Lifetime Warranties.

2 - Will be installed by a company that's been in business long enough, or is backed by a a manufactures that's been in business long enough for you to assume they will be around for many more years to actually honor that warranty if needed.

3 - I would suggest you stay away of companies that install generic products, like simple corrugated pipes and makeshift baseboard systems. They usually charge you as much as you would pay for a brand name, manufacturer backed product and the generics are simply not that effective. These generic system don'tt have important features like service portals, which will allow the system to be serviced and flushed periodically, air tight sealed sump pump pit to prevent the collected water to evaporate from the pit into the basement and keep kids and pets safe.

Please call a few more companies in your area, do some system comparison and some shopping. Don't let yourself be pushed into signing anything you are not 100% confident about.
Old 02-21-14, 06:02 AM
Join Date: Feb 2014
Location: USA
Posts: 10
Received 0 Votes on 0 Posts
Just found this thread.....I had an interior french drain system installed and had an efflorescence problem...read this thread


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes
Ask a Question
Question Title:
Your question will be posted in: