Questions tagged [vapor-barrier]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
1 vote
1 answer
93 views

mitigating radon in basement with joist & plywood floor

I bought a vacation home in the mountains and have found that it has a dangerous radon level (7.4pCi/L). The house has an 800 sq-ft unfinished basement, including a rough plywood floor over treated ...
user avatar
0 votes
1 answer
43 views

Vapor barrier under cut slab

My basement concrete slab has been cut to add some plumbing. Problem is that it was cut in such a way that there are no existing vapor barrier left to tie new ones into. Attaching photos for better ...
user avatar
1 vote
1 answer
52 views

Identifying thin plastic sheets between interior walls

I needed to run a cat6 cable through an interior wall between the living room and the office. Upon removing the drywall to insert a low voltage bracket, I realized there was a thin, opaque, plastic ...
user avatar
1 vote
1 answer
65 views

Can I use a ground trench as a concrete foundation form?

My city said that for my 2-1/2 story home, the foundation needs a 12 inch wide and 3 feet deep foundation with 3500 psi concrete poured within the mud wall (i.e., no need of foam board). I am planning ...
user avatar
0 votes
1 answer
40 views

Luxury vinyl flooring and above grade hot humid vapor pull

I've witnessed first hand that a strong vapor pull from a crawlspace up through the subfloor can happen when there is a big temperature difference. In this case a single room was cooled to 68 degrees ...
user avatar
0 votes
0 answers
15 views

humidity / heat transfer concerns screwing double layer of plywood subfloor together

TLDR: Two layers of plywood, 1/2" under 3/4", screwed together with 1 1/8" screws where there are no joists. Will the screws transfer thermal energy causing vapor pull, ruining the ...
user avatar
0 votes
1 answer
67 views

What is the most important component for the airtightness of a room?

I have looked at the UK building regulations and it says that timberframe cavities should be airtight to a minimum of 0.6 changes. This is for new builds, not renovations which is my case. Looking ...
user avatar
1 vote
1 answer
54 views

Vapour barrier for insulated, occasionally-heated Toronto shed?

I'm building an 8x12 garden shed in Toronto Canada (cold winters, fairly hot & humid summers). 2x4 construction, exterior Tyvek wrap, hardie siding onto studs, roof is metal standing seam over OSB ...
user avatar
  • 11
1 vote
1 answer
64 views

Insulation boards with foil facing outside - condensation issues?

AFAIK the best-practice for applying insulation+vapour barrier in cold climates is: inside -> inside wall -> vapour barrior -> insulation -> outside wall (exposed to the elements). If you ...
user avatar
  • 141
0 votes
0 answers
34 views

Insulating solid walls, permeable membrane vs solid insulation

I've got an integral garage being converted to living space (bedroom). Around half the longest wall and rear wall is below ground which is insulated and well drained from the outside. Front wall ...
user avatar
  • 2,819
0 votes
0 answers
37 views

For a floating floor - Is it safe to use an underlayment above an existing vapor barrier?

I have a concrete slab floor, and it was very uneven, so I placed a vapor barrier down (6ml poly) and then I nailed 3/4" plywood overtop. This fixed a lot of issues with the floor being uneven. ...
user avatar
0 votes
0 answers
112 views

How should I insulate my old brick house?

My house was built in 1920 out of a single layer of 8-inch thick hollow brick. I am looking to insulate the walls in the upstairs entirely from scratch -- there's no insulation on them at all right ...
user avatar
0 votes
0 answers
29 views

What level of damp proofing is needed before battening my garage walls?

I am battening my garage walls this week but have read so much conflicting information on what vapour / moisture control is needed. The garage is attached to the house, so one wall borders the house. ...
user avatar
0 votes
0 answers
23 views

Several layers of polyethyleen sheets as a vapor barrier under underlayment & laminate

I am putting 7mm laminate on concrete. I have underlayment (5mm) that requires >0.2mm polyethyleen (PE) sheet as a vapor barrier. Unfortunately, I couldn't get >0.2mm PE but got 0.16mm PE ...
user avatar
0 votes
1 answer
95 views

OK to forego vapor barrier under concrete slab if pressure-treated sill plate is used along with sill gasket?

Is it OK to forego installing a vapor barrier beneath a concrete slab (garden shed foundation) under the following set of circumstances? there will never be any flooring material placed on the slab ...
user avatar
  • 434
1 vote
1 answer
65 views

A creative Eco-friendly Underlayment for a metal roof? [closed]

I am building an octagonal cabin with a 200 sq ft metal roof (Grandrib 3) at a 30 degree pitch; the roof will sit on wooden strapping and will eventually have insulation below it contained by a ...
user avatar
0 votes
2 answers
98 views

How can I add more insulation to my finished attic walls without trapping moisture

I have a finished attic that has a kneewall insulated with fiberglass batts, insulation facing in. The batts fill the depth of the wall cavity completely to the end of the stud, there's no more room ...
user avatar
2 votes
1 answer
84 views

Do I need a vapor control membrane inside the roof if I have a breathable underlay outside?

I am a DIY'er working on a cottage in a remote part of the UK. I don't really have access to a professional roofer so I've just been having a go at it myself with some labourers. So we have ...
user avatar
1 vote
0 answers
73 views

is there anything wrong with using plastic sheeting under joists in a dirt crawlspace area?

background info: old farm house crawlspace with exterior perimeter walls made from boulders and cement skimmed to create a fall surface. joists under the main living space have batting type fiberglass ...
user avatar
0 votes
0 answers
114 views

Should I install a vapor barrier before adding drywall to my garage?

I'm refinishing my attached garage, and part of the job will be to install drywall. Currently, the walls have faced installation installed are are covered with pegboard. I'll be removing the pegboard ...
user avatar
4 votes
2 answers
368 views

Cost effective insulation for a 100 year old home?

My home is in central Indiana -- climate zone 5. It has lasted 100 years with no insulation at all. I've removed all of the super thick and heavy 3/4" cement sheet rock on the exterior walls and ...
user avatar
0 votes
0 answers
657 views

What type of insulation do i need to replace in my AC air vent registers?

We noticed we had mold on our register grills due to one of our AC unit not draining anymore in the attic (water was ponding in the pan); we had a remediation company come out and they told us we ...
user avatar
  • 1
1 vote
2 answers
211 views

Should I put a moisture barrier between a single ply of pressure treated (PT) plywood and a second non-PT ply when constructing a shed?

I am building a shed. The floor consists of 4x4 PT runners, 2x8 PT girders, and 3/4" PT Plywood flooring. Anytime in the past, when I have laid PT lumber next to non-PT lumber, there is mold/...
user avatar
0 votes
1 answer
286 views

Is Fiberboard sheathing under cedar siding ok with no vapor barrier?

I am patching horizontal lapped cedar siding on a 1950s house in Minnesota with fiberboard sheathing. I think it’s Nu-Wood. There’s no vapor barrier. I will have to put a vapor barrier per code where ...
user avatar
2 votes
2 answers
351 views

Vapor barrier on heated entertainment shed

i am building an 8x10 entertainment shed with a loft for kids to hang out and have sleepovers in, i will be heating it. I have tyvek and t1-11 it is on 4x4 skids on top of the Concrete patio and has 3/...
user avatar
0 votes
3 answers
279 views

Can a vapor barrier follow the profile of floor joists?

I'm renovating the 4th and top floor of a house built in 1906 in Rotterdam, the Netherlands. The house has masonry load-bearing walls and wooden beams. The current situation is shown in the image ...
user avatar
  • 183
1 vote
3 answers
883 views

Suggestions to hold floating laminate floor from sliding on vapor barrier installed over concrete slab

I need suggestions for keeping a laminate floating floor in place during installation on a vapor barrier over concrete. I was hoping to hear of good ideas to prevent this slip/slide effect on the ...
user avatar
2 votes
2 answers
655 views

How to insulate metal roof on shed and avoid condensation?

I’m fixing up an old uninsulated shed. The roof — built of metal sheeting on plywood, nailed to the 2-by-4 rafters — needs to be insulated. What is the best way to insulate the roof that avoids ...
user avatar
  • 389
1 vote
1 answer
317 views

Must we install a "moisture, not vapor" barrier, room-side, on an insulated above-grade portion of an exterior basement wall [closed]

Must we install a "moisture, not vapor" barrier, room-side, on an insulated above-grade portion of an exterior basement wall Can we forgo installing any " moisture, not vapor, " ...
user avatar
0 votes
3 answers
195 views

Humidity levels in new basement are high

I'm currently living in a new build in Ottawa Ontario for which I took possession in February 2020 ( I've been here for about 5 months ). The humidity levels in my basement have gone gangbusters in ...
user avatar
  • 39
0 votes
0 answers
34 views

Vapor Barrier Under Insulation on Attic Floor

My brother tore out the mdf tile ceiling of his cottage and nailed down ~1x6 pallet wood on top of the ceiling joists in the attic. There are large gaps in the boards. On top of the boards, he rolled ...
user avatar
0 votes
1 answer
56 views

Faced or unfaced insulation

So my house was built in 1957, I have shiplap siding and behind black boards that are fireproof. On the photo you can see the exterior wall where these boards are. Should I use unfaced insulation or ...
user avatar
0 votes
1 answer
165 views

Vapor barrier on Bathroom tub exterior wall(s)?

So I keep seeing conflicting answers on this. I'm renovating a bathroom that was torn down to the studs. On the exterior wall I have siding-tyvek-plywood sheathing-fg insulation inside studs. My plan ...
user avatar
  • 1,521
0 votes
3 answers
591 views

Densheild tile backer board use advise needed

I'm in the process of doing my bathtub walls and I'm thinking of using Denshield™ boards. My total area is 55 sq ft. I found 4'x8' Denshield™ sheets so I will need to buy two sheets to cover my area (...
user avatar
  • 49
0 votes
1 answer
85 views

Are glass textiles with PTFE coating used as vapor barriers for installation under the roof?

In construction in Central Europe are in use vapour barriers, in special cases more precise as vapour retarders. These enable the drying of building materials such as insulation, if moisture has ...
user avatar
  • 119
1 vote
1 answer
3k views

Should I use a plastic moisture barrier underneath a new deck to help prevent rot?

Our deck was 12 yrs old a lot of rot and we have torn it out. My husband is thinking of putting a plastic moisture barrier underneath the new deck. The deck is on a slope and consists of an upper ...
user avatar
0 votes
0 answers
30 views

Outside Sauna Build Moisture control any suggestions?

I am currently building an Octagon sauna that will double as a mobile bug out shelter that will be mounted on a trailer. I'm putting the octagon on edge if you can imagine so that when viewed from ...
user avatar
1 vote
2 answers
480 views

Insulating against brick in rim joist bay

I was hoping to air seal and insulate the rim joist in my basement. This is a balloon-framed house in zone 5, so the bays are open to the floor above. At some point brick and mortar were put in the ...
user avatar
  • 325
0 votes
0 answers
2k views

Another Question on How to Cover Up Exposed Insulation in A Basement Ceiling

I have read through many questions with a similar problem, but different circumstances than I have regarding this issue. The home is in Ohio so cold winters and hot summers built in 1997. I have a ...
user avatar
0 votes
2 answers
66 views

Deal with humidity in Garage with no vapor barrier

My garage slab has no vapor barrier and I live in Houston which is often wet and almost invariably humid. Water seeps up through the concrete and humidity is always pretty high in the garage. Power ...
user avatar
  • 138
3 votes
1 answer
2k views

How should I prepare a log home for vinyl siding?

I am going to side over a log home. Some of the logs are deteriorated and the maintenance has not been done for years but for the most part the logs are solid. I want to fur out the logs with 1 x 4 ...
user avatar
1 vote
1 answer
36 views

Fireplace/brick foundation

I'm rebuilding my garage and have planned to install a footer, full brick base, and full brick wall behind a wood burning stove. I'm planning to have the "base" be mostly standard concrete block with ...
user avatar
1 vote
1 answer
286 views

With a vapor barrier installed, how critical is slashing/destroying faced insulation underneath?

After installing a vapor barrier, forgot to slash/destroy the faced batts of insulation within some wall cavities and/or ceiling areas. Am I in "OMG deep doo-doo" for not slashing the batts, or ...
user avatar
  • 21
0 votes
2 answers
130 views

Crawlspace encapsulation

This past weekend I recently had to fix the flooring of my family cottage. In a heavy-traffic side entryway, the plyboard floor was bending when you walked over it. We opened up the floor to see ...
user avatar
  • 103
0 votes
1 answer
117 views

Can the vapor barrier between a dry floating concrete slab and linoleum flooring be foregone?

I have a two year old house that sits on an 8" concrete floating slab. The slab is insulated below and around the side. The floors in the house are unfinished. That is, the concrete slab is ...
user avatar
0 votes
1 answer
142 views

Can I install Insulation board in the interior wall with House wrap on the exterior

I am insulating a shed as a wine cooler. I have house wrap on the outside. I will install unfaced batt insulation between studs. Can I then install foam insulation board under the drywall? I am ...
user avatar
  • 1
1 vote
2 answers
113 views

Concrete vs suspended floor over vapor barrier

Our house has a sizable crawl space large enough to use as storage. The space has no slab covering it, but due to radon issues, it does have a vapor barrier to maintain a suction for the radon ...
user avatar
  • 63
1 vote
0 answers
44 views

Unfinished basement in Georgia townhome; would vapor barrier on interior trap moisture?

I have a town house that is a middle unit on a slab. The back wall is above grade, with exterior windows and door. The sidewalls abut adjacent units, so there is no wall in contact with soil for the ...
user avatar
  • 603
1 vote
3 answers
97 views

Redoing insulation in the basement of the home I recently purchased

I recently purchased a home and have begun to do renovations on the basement. I am starting to look at insulation and so I have been researching what the best way would be to do that. The problem I am ...
user avatar
0 votes
1 answer
857 views

Vapor barrier behind electrical panel?

My electrical panel is mounted on bare studs of an exterior wall in my attached garage (living space above). The garage is not insulated and it does not need to be (except for the ceiling which will ...
user avatar
  • 664