How to Seal a Room With Foil

If you, or someone you know, could do with a safe room, then try this: buy a roll of foil from a plumbing shop, your local hardware, or order it from a company that specialises in this type of product. Use it to seal the floors, the walls, even the furniture. Building wrap, designed to stop vapours, is what you are looking for. Brands in AUS include: Vapastop, and Kingspan; In Europe: Pure Aluminium Barrier Foil; and in the US: Dennyfoil 245. (I’m sure there are some more trusted brands that myself, and my readers, would love to know about, so be a Gem and leave your suggestions in the comments below, and I can then update this post to include them.)


Important: The types that don’t have an insulating blanket attached to the outside are imperative for this project, because the blankets are treated with fire retardants (aka: the asbestos of our time!)—we want just foil for this project.

When looking for heavy duty foil, another unsuitable product people may find is a type of builders’ foil; it has blue paint on one side, and foil on the other: the blue paint is solvent based. So, know this: most people who’re sensitive to chemicals won’t tolerate this well. For me, trying this product was a disaster: when I moved into my first specially chosen rental property in Portsea. There was a brand new kitchen and it was a huge problem for me. I couldn’t stand over the kitchen counter without experiencing breathing problems and headaches, which was terrible as I had a seven-year-old to cook for. So, at my Immunologists suggestion, I had a friend seal the underside, exposed parts with builder’s wrap. It was the only heavy duty foil to be found at Bunnings. This affected my eyes and nose, burning them when breathing the fumes in (even though the painted part was face-down against the chipboard). That’s when I found Vapastop, it’s just foil with nylon webbing on the inside, giving it that heavy duty-ness that is needed in high traffic areas. (Builders’ foil can be used to seal chemically vaporous areas where tiles are to be laid; this is a good option if you want to seal in the chemical residues left over from carpet that has been pulled up, or something else acting as an irritant to the occupant.)


(I’ve used this for many things, even wrapped a mattress or two in it (DON’T DO IT before reading this post.). This foil is so handy for us chemically sensitive Aussies, that there is even a woman who used it to wrap the plaster cast on her broken arm so as to put a stop the chemicals emitting from the plaster that were making her ill.

You know that silver accessories have been in fashion for a while now, don’t you?

Vapastop is perfect for small jobs, or anything that is soft and needs a bit of flex or has corners that need covering: furniture, chipboard, anything that outgasses fumes. (Just remember, anything that’s got a fabric component needs to breathe, or it may go mouldy: a la mattresses! So it’s a temporary measure.)

Most recently though, in this house of mouldy horrors, I’ve used Kingspan to seal the floors in two bedrooms. One was the room where the concrete slab was drawing in water from the gardens outside; therefore creating dampness, and inviting it’s best buddy in with it: mould. (In this house, every time it rains I can smell an earthy smell, my breathing is affected and it’s just plain rotten around here, and all my plans—writing, working, living, cooking—turn into uneventful mush made from pain, irritation, sadness and frustration.)  The other was in a room where new floorboards—not real wood, but fake wood, the chipboard kind—have been laid. The door had been kept closed over the last summer we had, with the window open also—so as to outgass them—but they were still a problem. (In case you don’t know chipboard contains glues made from formaldehyde, and these take years to outgass. (For those who are new to reading this blog and/or reading about chemical sensitivities, outgassing is the process where a  substance, material or product—say a new kitchen, or couch (even fresh paint or mould)—releases vapours into the surrounding air. These are called Volatile Organic Compounds (VOCs) and when too many of them build up inside an inclosed space, they can cause the occupant(s) health problems such as headaches, asthma and/or chemical sensitivities (or MCS as it is also known as). For a person sensitive to those chemicals they can cause or worsen serious health problems. And that’s what happened to me.) So I did what I’m good at: smothered the pain causing area with foil!

The Kingspan foil is made by a company who specialise in building wraps for ecological buildings. And, even though it has its own blanket made from polyethylene, this is sealed in between two pieces of heavy duty aluminium foil. It comes in a roll, and needs to be cut by someone who is not sensitive to chemicals, or if you are chemically sensitive, wear a mask just in case. It comes in two thicknesses: 6.5 and 8 mm. Both of these rolls are 1350 mm x 22.25 m. Kingspan are transparent about what goes into their products—all their Material and Safety Data Sheets are available online, here. And I’ve spoken to them, and they even recommended the best product to use: Insulbreak! Aircell has tiny holes in so that houses can breathe, so it’s not a good choice for this job. One of the reps even dropped some samples around to me. How kind was that?

(Just so you know, when you’re ringing around, trying to find a company that sells a particular product that is suitable to seal in chemicals created by certain other companies who manufacture certain other products that release these chemicals, some people can try to treat you like a Right-Royal-Weirdo, but DO NOT listen to them, just keep searching; then you will find an environmentally sustainable company (like Kingspan) who also care about *sustaining humans* and their health, as well as our magnificent Earth! And this company will know exactly what you are talking about, and they will understand exactly why you want to do this. And they will help you… )


You’ll also need a roll of foil tape. Here’s some available in AUS, some in Germany, and some in the US.  Another dynamically useful product that I’ll share with you! You’ll either need a pair of gloves, or to be extra careful: the tape has sharp edges that cut similar to a paper-cut but much deeper.


(Note: if you are a renter, and/or you don’t want to create any damage, then you also need a roll of painter’s masking tape to stick under any areas where you will stick the foil tape: it leaves behind an unsightly glue residue. The masking tape does not, so this will protect any areas where you want them to be left clean when it’s time to remove this temporary ‘renovation’.)

Follow these steps (or create your own from this template):

Measure the area and make sure you have enough materials.

Clean the area, and let it dry. The concrete floor that was sealed here, never got to dry, because the nature of this concrete is that it’s not sealed correctly around the edges of the slab: shoddy workmanship. Through research, I’ve found that a slab needs to be sealed correctly or it creates honeycomb like pockets, which draw in moisture. And this process will happen:

Natural soluble mineral salts are commonly found in soil. When rising damp occurs, nitrates, chlorides and efflorescent salts migrate through the masonry in solution and accumulate on the wall surface as a white powder.

These salts are hygroscopic and attract moisture from the atmosphere, particularly during periods of high humidity, and give the effect of persistent dampness and associated damp smells.


The same thing has happened here:

Oh, so it’s not really fairy dust… It’s salt of the Earth

But come winter, autumn and summer rains, there is this:

And then came the rain. Again. And again…

(An eco-builder said the best solution would be for the landlord to have the gardens dug out, away from around the house, and then have tar poured into place against the edge of the slab. That’s a great idea; however, only if I’m not renting, and living here. (It was at my request that the carpet in this room was pulled up. Can anyone imagine what would happen to the carpet if left on top of this? Answer: more mould. Even a person without sensitivities to chemicals can be made ill by living around this.) There are other solutions to the problem. A temporary one was to paint the floor with concrete sealer, and then lay flooring over the top. Still not ideal, as it doesn’t solve the dampness, and the paint may peel. And can’t it be done unless the floor is dry. And, if solvent based paints are to be used, I can’t be living here, or have any of my belongings in the house because solvents are the number one chemical that I need to avoid. When I recovered, a few years back, this was the only chemical left that effected me.)

Next step: the damp patch was sealed with foil adhesive tape. (I know, from a building-biology type of perspective, it’s so wrong! Theoretically, this should cause the dampness to rise up the wall, if it hasn’t already. Nothing would surprise me with this house.) And, I had the owner’s permission to do this; it’s only a temporary measure!

A Building Biologist’s Nightmare

Note: don’t forget that the adhesive on this tape really sticks and it leaves that yucky-gummy residue behind that’s always a pain under the nails to scrape off, so you don’t want to put it someplace where it needs to be removed later and still look clean and nice. (Especially if you are renting.) Put painters masking tape over the surface first, then put the foil tape over that. (Painter’s tape is designed not to leave yucky gunk behind, or pull off paint and other surface coatings when it is removed. That’s why painters use it around windows and mirrors.)

Next: (This step is optional) Lay a down a layer of foil underlay with the foil side facing down (we used one from here, called Lamilay). The foam on the top is a type of plastic foam: polyurethane, which is also treated with an antibacterial and anti-fungal. I didn’t worry about this at all; as you can see, it’s about to be sealed in. And I had a mask on, of course! This product is designed to stop moulds from affecting the floorboards, which are supposed to go over the top of it. This was done so that the landlord of the property can lay floorboards straight over the top when I move out (chipboard floorboards! *Nice*.).

Next step: cut the Insulbreak to fit. A Stanley knife will be handy at this point. Then, tape it in place using the foil tape, while being careful not to cut your fingers on the edges if it.

Remember, covering anything with foil is usually a temporary solution. Foil wears away; it flakes off and it tears. Just ask my dog about that.

The good things is: you can slap another piece of foil tape over the top of any tears. (I know, it’s a weird life!)

Warning: don't let dogs do 360's on the floor, or you will need to do this!

Warning: don’t let dogs do 360’s on the floor, or you will need to do this!

Another thing I like: it’s actually really soft to walk on, and it reminds me of what it’s like to have carpet: it’s warm; my feet are comfortable touching it in winter; and it’s not achingly stone cold, like tiles can be (just for breathing difficulties, I’d still prefer tiles any day!).

Update 12 Feb 2013 (9 months later)

Know this: it all turned to shit little pieces of foil, flaking about my house. Everywhere. This is awful for a person who bases the order of their world on the tidiness of their house! But, for future reference, I’d love to know how other people have dealt with having foil on the floor while still using it to walk on it. Please share your ideas with us… on the use of foil, or anything really.

Useful options I can think of:
  • A wool, jute or cotton rug(s) over the top (I did buy a large wool rug, which–nine months later–is still outside airing);
  • Tyvek? This could be slippery though

And that’s as far as my imagination could stretch. If I were to stay living in this house, I’d probably just layer another layer of Kingspan Insulbreak over the top. Kind of like an insane version of floor lasagne, which instead of it being a lasagne that gets eaten, it’s actually a specially-self-designed-floor that stops my health from being swallowed up whole by the Toxic Mould Goblin, himself! So yeh, it’s a lasagne for a goblin! Made with foil.

My Big News

And, here’s my big news: I’ve moved out. Not officially, I’m still doing a mould decontamination protocol of all my stuff, but I have found, signed the lease, and taken the keys, for a property near the sea! Hooray for me. See, there is something good about mould after mould after mould exposure. Who woulda thunk? I will blog more about this miraculous journey that I’m on, but know this: I’m on my way out of the Labyrinth of Chemical Sensitivities. Now I can officially say goodbye to 2012; and finally, I can leave the hell of it all behind.

Peering back through my retrospectorscope at the foil renovation situation, I can now see that it was an awesome, if not such a weird thing to do. It stopped the damp coming up through the concrete when it rained (but it didn’t stop it coming from the roof, or the laundry, or from out in the closed in driveway/slash fernery), so the room where I kept my clothes had no visible mould growing in it during the last nine months of my stay. Before that, it was on the windows and the walls.

Also, through the retrospectorscope: it was a great thing for my landlord, now he is free to do what he wants, which is lay down floating floor boards to match the rest of the house. (I’ve blogged before about how these are made from compressed wood, sealed with glue that contains formaldehyde and monkey knows what else!) If I had my way, it would have been tiles! A sure thing for anyone sensitive to chemicals cause those tiles will surely put out!

So long as your landlord/real estate agent agrees, this is a win/win awesome, yet temporary resolution for any area that’s outgassing chemicals that are effecting someone’s health. More on this solution from renowned environmental sensitivity expert Pamela Reed Gibson:

“The person should inquire about the pesticide history of a potential home by questioning the landlords, builders, or neighbors. Formaldehyde impregnated building materials such as particle board emit considerable formaldehyde particularly in their first year and continue to outgas for ten or more years. Better construction materials include exterior grade plywood, as it contains a lesser amount and a less toxic type of formaldehyde (phenol formaldehyde rather than urea formaldehyde). Interior grade plywood may outgas formaldehyde as much as the particleboard. Cupboards and other visible particleboard products can be sealed with less toxic products designed to prevent outgassing of fumes. However, people who have tried this suggest that it might be safer to simply replace particleboard or other composite board cupboards with old-fashioned metal or glass shelves and cupboards or to cover the particleboard with aluminum or steel foil, whatever is tolerated best.”

You can read more about Understanding and Accommodating People with MCS, here

More information on mould

Mould Fact Sheet

The US

Mould Myths

Allegictolifemybattle: a mold surviver’s blog

New York City Department of Health and Hygiene 


WHO/Europe: Biological Indoor Air Pollutant – Dampness and Mould

More Information of Formaldehyde

Doctor Jekyll and Mr Formaldehyde 


Posts coming up next:

My Hammock Review ~ and sleeping in the great outdoors…

Video Vlog: Nasal Filters

How to Find a Suitable Rental Property

Healing the Gut II

And: Acceptance of My Wonderful, Gratefully Received Blog Awards :) 

Michellina Van Loder is a Professional Writer, Journalist and Blogger. This is where she shares her tales about trail blazing her way out of the Labyrinth of Chemical Sensitivities and Mould. This is also where you will find the latest Research on related topics.

About Michellina van Loder


  1. Hi Miche, just to clarify, is the kingspan product you mentioned just a vapour barrier, or is the polythene bit in the middle for insulation as well? Someone we know recently used an insulation product that had foil on both sides and some sort of blue rubbery stuff in the middle, I’m not sure of the brand. We thought we might try it for insulation in our caravan, as the typical polystyrene caravan insulation does not suit my health. Is that something like what you used on the floor? Also, when I read the kingspan website it seemed their foil tape had a fire retardant, are they all like that, or was it not a problem for you? Another thing, I am not very practiced in ringing companies to ask questions about their products, what sort of questions did you ask?
    Thanks, Eliana

    • Michellina van Loder says:

      Hi Eliana

      The kingspan Inulbreak 65 is a 3 in 1 type of building wrap (caravan wrap :); it serves as insulation, vapour barrier and a thermal break. The thermal break could be good in your case because it absorbs and reflects heat, therefore, it increases the building’s R Value. You can download the PDF on this page:

      I found this product via Quin Wyatt who designed our Allergy-free, Eco-Friendly house we’re about to build. We will be using it to wrap the house in. i’ve tested it extensively, and know that I’m okay with it. I like that the inner layer is covered with foil on both sides. There’s also an insulation product called Earth wool, which can be used in conjunction with the Kingspan Insulbreak. It’s fibreglass and doesn’t have the colours and additives that conventional synthetic wools do. We are using the Kingspan, then the Earthwool, then sealing it all in with a plain Vaperstop foil product. Then putting Modakboard instead of plasterboard.

      I’ve heard that there is a product called Neemaboard that can be used in caravans instead of MDF and all that other stuff. It’s PVC though.

      The foil tape I use is different. It only has the adhesive (the spec sheet says it’s a synthetic rubber type adhesive), which once stuck down is fine (for me, anyway. i always have someone else do it, so it’s easy for me to sit back and say, “i’m fine with it.” I’m not the one breathing it in!). It’s the Tesa brand:,i.html

      The one from the US, Denny Aluminum Foil tape, is also made by Tesa, however they reckon theirs has a natural rubber adhesive:

      (I don’t care if something is natural or synthetic. I just want to use products that are not respiratory irritants, and don’t impact on our earth… )

      I’d stay away from the ones with fire retardants. It’s great that you’ve done your research, though.

      Asking companies questions:

      Pretend you’re a journalist. That’s what i do :) Just kidding! I am a journalist so that helps. However, when ringing to ask things on a personal level, and to do with protecting my health, I get a little nervous. This is what helps me:
      make a list of all your questions. Even the silly ones (you can cross them out later if you think they are terribly useless or rephrase them.).
      Make a list of all the places you want to call and their phone numbers
      Bullet point their answers so you can compare them after

      Here are my questions:
      Hi, do you have ‘such-and-such product’?
      Great, I need one that doesn’t have ‘such-and-such as an ingredient’. (For me, it’s usually petrochemicals and solvents, possibly fragrances too.)
      If you get a vague answer like, “Come into our showroom… “, say, that you have a medical condition that stops you from being about to go out where there might be fragrances or solvents and petrochemicals from spray deodorants in the air, and you need to speak to someone on the phone. (Tell them you have to wear a mask. (This is the part where they will become emphatic and try to help, or they will go weird and shut down, giving you more vague answers.))
      Obviously, we want to be dealing with empathic sales people, if they are not understanding, call someone else. Do you know how many businesses and people there are out there who want to help us? Lots! And that’s why you need a list of businesses to call. If you work through this list, by the time you get to 3 or 4 on the list you’ll have found someone who wants to help. (And you will become very practiced and good at being assertive and doing what you need to do to protect your health!)
      I also ask if it’s possible to get a small sample or piece of the product so you can test it. (remember, most businesses want to sell their products, and even if they don’t usually give out small cutoffs of their products, they will often make an exception if you explain that you need to check if it will be okay for your health.)
      Explaining how you test a product i.e. put a piece of it near you and see if you are okay when breathing it, can be helpful in getting the business to understand why you need to do this.
      I never ask people if a product smells because being able to ‘smell’ something is always going to be subjective;; and seeing it’s about the chemicals not the actual smell, it doesn’t matter too much if they can smell something or not.
      And, finally, I nearly always ask for a Material Data and Safety sheet if i run into someone who is not being helpful. They are often available on their websites but just asking them is showing that you are holding them accountable. Here are the Data sheets for Kinsman:
      :) You’re welcome

  2. I just came onto your post and found it quite interesting.I am also associated with airductmanagement.It gives services like Air-Duct Cleaning, Dryer Vent Cleaning,Odor Removal Las Vegas,Fireplace Cleaning Las Vegas.Thanks again for writing such a good post.

    Explore more about Air-Duct Decontamination Las Vegas

  3. twoteacups says:

    I am trying to seal in a leaky window temporarily that is bringing in asphalt roof tile smells into the house. I remembered this post and now I’m looking for aluminum barrier foil! I’m confused about your process though – did you use 100% pure aluminum barrier foil (doesn’t have any antimicrobial, waterproof, insecticides, etc) and does that even exist, or did you use foil blankets that were insulated? Also what’s the difference between using this and plain old kitchen aluminum foil? Is it thicker? It seems that pure 100% aluminum barrier foil is hard to find in local hardware stores here.

    • Michellina Van Loder says:

      Hello twoteacups
      [just a sec, while a make a cuppa]

      Now, personally if I was sealing something temporarily (like for only two weeks) I’d use ordinary foil from the kitchen: folding it in half (so it’s doubly strong], then put it along, on top of the gaps, covering the gap each side by about a 10 cm (aprox 4 inches) overlap–or as much as room allows, then seal the edges down with painter’s masking tape (which is available from most hardware stores; and it won’t pull the paint off or damage the surface when it’s taken it off), making sure to seal around all the edges.

      To seal the floors, I did use foil blankets that were insulated; but, they cost a bomb because I had to buy the whole roll. Around the edges where it had to stick to the floor, I applied the same process above but only put the masking tape to seal it down. (The foil blankets have now been removed, MDF type floorboards were laid in that room–and the bedroom door is kept shut–and I’ve moved out but a lot of my stuff is still in a room at the other end of the house. The foil blankets had a heap of mould under them (So I was told); what with the concrete leaking water and all.)

      Another option would be to use the masking tape then put foil tape over the top. The foil tape will have an adhesive under it that is quite strong odour wise and, also sticky wise; the odour will disappear once it is stuck down but the glue will adhere to whatever it is stuck onto (needing solvents or ‘natural’ orange based solvents to remove it). Using the masking tape underneath will protect the surface from the foil tape’s glue.

      This is the foil tape that I know of in the US: And this is one in that’s available in Toronto:

      3M (the company that makes my masks) make one too:

      (In Australia, I buy mine from Officeworks, which sells stationary products, and Bunnings, which is a big hardware store. In the past, I’ve bought it straight from the company, in a box of 12. This way it hasn’t been sitting in amongst the chemical based products that the bigger stores sell. The brand is PPC, made by Precision Paper Coating, an Australian made and owned product: It it used to by air-conditioning installers to seal the air-vents in air-con units. Also, it’s used in roofing insulation.)

      Here is a list of safer building products from reshelter, including the foil tapes:

      Most insulation products, as in foil blankets have fire-retardents, or/and antimicrobial, waterproof, and possibly, insecticides in it. The blanket I used was from an Ecologically minded company. It still had the fire-retardent in it as that is the law over here but it was sealed with foil on both sides; so once it was stuck down, it didn’t emit anything. Cutting it was a problem (the fibres/dust were problematic) but I wore my mask, and had a friend do that part anyway. The foil tape, though, should only have glue; but who knows with companies these days?

      Because moisture may come through the cracks of the windows, when removing it, the area would need a good clean with bicarb and vinegar (lots of vinegar). I would also use paper towels–or old rags–that can be thrown out afterwards.

      Hope that helps? Good luck, and please post your success here, so that others in our position can gain ideas to solve their ‘challenges’ also.


      • twoteacups says:

        Thanks so much!! :) I actually managed to find the same aluminum foil tape you mentioned (ShurTape solvent free) @ Eco Building Resource in Toronto I’m so glad you did this huge write-up it’s been very helpful! I didn’t want to splurge on a huge roll of that foil barrier so I am going to try plain aluminum foil since the window is not huge – I will try your method. I think I will leave it up for a week and then reapply a new “set” to discourage any mold build-up. I hope that the roof outgasses no more than 2 weeks because the smell is terrible in the hot sun :( I couldn’t find anything online that states how long a roof takes to outgas. I never expected the smell to come into the house! I also noticed that an unsealed doorway in the house is drafting down the smell too and I’m trying to find some kind of (safe) insulation to stick around the cracks and maybe I will just put the aluminum foil tape all around the perimeter as a temporary measure (over painters tape)

  4. Congrats on finding a new place!

    When I first moved in to our current apartment, I got really sick. I have no formal diagnosis of allergies or sensitivities, but cigarette smoke has always made me horribly ill. We found out the man living above us smoked, and that’s what was making me ill. Luckily, our maintenance staff came in with – da da da! Foil! And covered any cracks (around pipes, etc) with foil and tape. In the long run, they eventually banned smoking indoors. But foil was my hero.

    • Support says:

      Oh, that’s awesome. No, not the smoke effecting you, but the use of foil. It’s so handy. Just watch out for covering any areas that could get moist, cause then it’s a trap for mould. Even though that is what I used it for: covering mould, it saved me from not being able to use that end of the house. And maybe all my clothes, I’m not to sure yet. I am trying to air things in the sun before taking anything with me. Thanks for the congrats; I feel better already. :)

  5. Michellina Van Loder says:

    Absolutely, it’s a last resort, temporary solution. It’s a pity, the owner of that house does not care so much; he just wants to renovate and sell it. (Notice, I say ‘that’ house, not ‘this’ house? I’m out! Just wait for my next post, you will freak out (in a nice way)!)

  6. You have to be careful with sealing a room with foil to make sure that moisture doesn’t get trapped behind the foil and cause mold to grow.


  1. […] will we?) And hey, don’t forget my motto: if you get stuck, bring out that trusty old roll of foil, and painter’s masking […]

Information, products and views presented by guest bloggers @The Labyrinth are not necessarily the same as those held by this blog's author, Michellina van Loder. Reviews are my own personal opinions (unless stated otherwise); and satire is used throughout personal posts. Any health topics discussed are not to be taken as medical advice. Seek out medical attention if needed and do your own research; however, you're welcome to use mine as a start.
Translate »