Posted by Matt on 6/1/2015 to Crawl Space Vapor Barrier
DIY Crawl Space Vapor Barrier InstallationInformation on crawl space insulation can be found here- Crawl Space Insulation Here is a straight forward step by step guide to installing a quality crawl space vapor barrier in your home. These are broad guidelines for you to follow that will apply to all crawl spaces. If you need additional guidance for more specific problems please contact us 864-223-7800.
Step 1- Assess your crawl spaceBefore you do any work in your crawl space you should assess all areas, conditions and problems. This will help you later to know exactly what your up against.
Step 2- LightingYou may not have thought that installing permanent lighting in your crawl space would ever be a benefit, but if you want to solve your crawl space problems then proper lighting will be a useful aid to your efforts. Depending on the current conditions of your crawls space, I would suggest you first install temporary lighting and then wire in a permanent solution once all moisture and water problems are resolved.
Step 3- Clean out and prep workRemove everything that is not dirt or attached to the house. Most often crawl spaces are the dumping ground for building and remodeling debris, all of it must be removed to avoid problems with odor, mold and or punctures. No matter how strong the crawl space vapor barrier is there is a possibility of punctures of sharp objects like crushed rocks, broken concrete and metal debris is not removed. IF it can not be removed or is far to large or numerous to remove you can use a protective underlayment like the Felt 550™ to prevent damage to your investment.
Step 4- Measure your crawl spaceYou can guess at what you need to save time, but when it comes time to spend your money you will need to be accurate. To get a proper picture of what you will need for water control, a crawl space vapor barrier and a proper crawl space dehumidifier you will need the following information:
- the length of ALL your foundation walls
- the height of ALL your foundation walls
- the location of the lowest point in your crawl space
- the location of your access to the crawl space
- size of your access
- do you have any water problems? have you ever seen ANY amount of water standing in the crawl space? are there stains on the foundation walls?
- does your home have air conditioning?
- does your crawl space currently have foundation vents to the outdoors?
Step 5- Product selectionResist the urge to make Step 5 the first step. Here's why; you should not make the crawl space fit the products, you should select the products that fix the crawl space. Certainly cost is a concern for most, but if you select a crawl space vapor barrier on price alone you will get what you pay for. Our recommendation assumes the reader: wants their work to last as long as possible, product quality is a concern and results are a must. Find the recommendation at this link- Crawl Space Vapor Barrier Selection From here it's time to get grizzly and fix that mess under your home. The final 5 installation steps are as follows...
DIY Crawl Space Liner Installation
Step 6- ToolsI am sure you already know, but I am going to say it anyway; it is so much easier, faster and cheaper to do ANY project when you have the right tools. Here are some tools to consider:
- crawl space shovel
- crawl space pick axe
- crawl space knife
- replacement blades
- 100' tape measure
- hammer drill (not a drill with a "hammer" feature)
- reciprocating saw (for plumbing work, cutting roots and buried debris)
- screw drivers
- wire staples
- electrical cords w/GFI
- organic mold cleaner
- crawl space broom
- small vacuum
- Heavy workshop paper towels
Step 7- Foundation wallsThis is the area that has the most fluctuation in install procedures from one company to another. I will tell you how we do it and then you will have it to compare to the many other variations. Some of the other procedures seem faster and better on paper, but do not pan out in practice. My example crawl space is going to be a rectangle, 30 feet wide 60 feet long and 4 feet 3 inches high and we will be installing 12 Mil GuardianLiner™ In the procedure we recommend, you will install the walls first, but you must figure how your floors will lay before you can start. Facts:
- In our example our crawl space is 30' wide.
- The GuardianLiner™ is 13'4" wide.
- For best results, floor seam should overlap 10-12"
- To cover the floor width we will need 2 pieces of GuardianLiner™ with the width of 13'4" side by side
- 13'4 + 13'4 = 26'8" minus the 12" lap seam we can cover 25'8" of floor width with two pieces of GuardianLiner™
- We have a 30' wide crawl space, we have 25'8" of crawl space vapor barrier to lay on the floor.
- 30' minus 25'8" leaves us 4' 4" short from covering the entire width of the floor.
Step 8- FloorThere is not much left to explain here. One advantage to splitting the floor width shortage of the crawl space vapor barrier to equal amounts on each side is your center seam will meet at your row of support columns so cutting around them will be much easier. Keep your vapor barrier pieces square to the crawl space and taking your shoes off will lighten the clean up work later. Here is a video on how to install a crawl space vapor barrier- Installing a Crawl Space Vapor Barrier
Step 9- TapingThe Waterproof Seam Tape™is designed to work with the above mentioned crawl space vapor barriers and will not come loose when it comes in contact with water, this is very important because many "crawl space tapes" do just that. Take your time and remember to keep the crawl space vapor barrier square to the crawl space when you are taping
Step 10- Conditioning the airA conditioned crawl space can be accomplished a few different ways, the important part is to DO IT. Conditioning a crawl space is THE reason the crawl space needed to be encapsulated, so don't skip this part to save money. Would you buy a pool and not fill it with water because it was not included in the price or it would make the cost of the pool less expensive if you left it out? Conditioning can be done with a quality crawl space dehumidifier or by using your existing air conditioning unit. Both options have their strengths. The best way to know which is best for your home is to get a moisture management plan for your crawl space. You can read more about a conditioned crawl space here- Conditioned Crawl Space
i have hard foam insulation glued to all the foundation walls already. I want to put the 20mil vapor barrier in and tape it to the front of the hard foam insulation. Will this work. I don't want to remove the foam insulation.
Megan Spooner 9/22/2015
Quick question: put the vapor barrier over insulated foundation walls? What happens to moisture from floor creeping between the liner and insulation? THANKS!
It is not recommended to tape, fasten, glue or otherwise attempt to attach the barrier to any kind of insulation. The problem will be that the method of attachment will only be as strong as the two surfaces attached too. Tape will stick to ridged foam for a short time. In every attempt this idea will fail. Removing ridged insulation from the foundation wall is not necessary. However, you will need to remove a portion of it so you can attach the barrier to the foundation wall. See this article- http://crawlspacerepair.com/blog/installing-rigid-foam-insulation-with-a-crawl-space-vapor-barrier/ <br> Matt
I am looking for advice on taping the floor liner around my sump pump tank. My tank sticks up out of the ground about 3" and I am going to pour concrete on top of the liner, do you have a video of this method?