Colder weather - draught proofing 💪

[lizziecupcakes]

Hi all, how’s your weekend going?

I’m in the process of draught proofing the house now asap. The temperature is expected to drop in the next week or two.

Some of you recommended draughtex before. This is their website.

Is it safe to order from them directly on their site, or can I buy it (cheaper) elsewhere? Just wondering if anyone bought directly from them?

I am thinking of getting the samples first too.

My other question is, do you think I should fill all the gaps? Originally I was going to place thick rugs down with anti-slip that’s sort of insulating, and then around the rugs I was going to add the draughtex. I don’t know if this will be infective though ??

Thanks all!

 

[fernicarry]

The website doesn't say what its made of but looks very like backer rod which is used for gap filling before applying caulk. If you can get it in the right colour, then a generic backer rod would probably work out cheaper for the sort of length you're going to need. Get samples of both and see which one you fancy using.

My approach for draft proofing the ground floor is to staple a breather membrane underneath the floorboards and then push a layer of natural insulation up between the joists. It made quite a noticeable difference to the comfort level of the living room last winter. I'm now doing same for the back room which has a lot less clearance under the joists so I'm having to dig out a channel in the bare earth as I go along. As unpleasant as it sounds...

If you can get under the floor then this will be cheaper and more effective but takes quite a bit of effort.

 

[Cubist]

Sorry LCC but that a very definite L No No from me.

That product is almost certainly a synthetic rubber material that in all likelihood will not easily accept a colour other than its natural black or dark grey - if its white then only a paint will cover/hide it. Apparently its sold in different diameters and again in all likelihood you would need a supply of both their 3mm and 5mm product and may even need something larger.

Before you go any further though, where exactly would you plan to use this stuff? I would urge you consider Caulking Cotton, as I recently recommended to OverlanderMatt for his hall floors. I have made extensive use of it around my home to close gaps of 1mm to 20+mm, it is ludicrously cheap and just as easy to use as that Draughtex stuff.

 

[lizziecupcakes]

My approach for draft proofing the ground floor is to staple a breather membrane underneath the floorboards and then push a layer of natural insulation up between the joists. It made quite a noticeable difference to the comfort level of the living room last winter. I'm now doing same for the back room which has a lot less clearance under the joists so I'm having to dig out a channel in the bare earth as I go along. As unpleasant as it sounds...

If you can get under the floor then this will be cheaper and more effective but takes quite a bit of effort.

This is interesting!
I really want to add floor insulation but I am just unsure about the issues with condensation and a bit nervous about causing it and subsequent then rot etc. i think I have about 15cm depth in joist (maybe more?) - I can’t remember but will check tomorrow.

What is the natural insulation you’re using? And what product are you using for the breather membrane? Is the breather membrane hanging abit below the joists or is it right up against the joists? I have no idea how i’d add the breather membrane right now. Is it something like this on youtube?

I was going to see how this winter goes with the gap filling products, but it seems Draughtex might not be popular. I will now reconsider!

 

[lizziecupcakes]

Sorry LCC but that a very definite L No No from me.

That product is almost certainly a synthetic rubber material that in all likelihood will not easily accept a colour other than its natural black or dark grey - if its white then only a paint will cover/hide it. Apparently its sold in different diameters and again in all likelihood you would need a supply of both their 3mm and 5mm product and may even need something larger.

Before you go any further though, where exactly would you plan to use this stuff? I would urge you consider Caulking Cotton, as I recently recommended to OverlanderMatt for his hall floors. I have made extensive use of it around my home to close gaps of 1mm to 20+mm, it is ludicrously cheap and just as easy to use as that Draughtex stuff.

Thank you for sharing!

I am planning on putting the Draughtex in the downstairs floor areas - living room, dinning room, hallways. Maybe the kitchen, although that’s mostly boarded with some sort of cork material and vinyl. The areas under the bottom cabinets are bare floorboards though.

I will check out Caulking cotton. Has it been good at insulation? Keeping the draught away?

Also my floorboards are very cold and i am constantly in slippers. They’re not sanded or stained/varnished yet so I’ll probably wear my slippers for a good while now until they are! But i am longing for warmer floorboards and to walk barefoot in my home. The luxuries in life!!

 

[lizziecupcakes]

@Cubist I had a look at caulking cotton - is this the method used on boats? where did you use it in your home? ChatGPT tells me it’s not reliable, but i’d rather take the advice from a human haha. It also makes me wonder how you clean your floors with the cotton caulking in too?

I also found this site… if you go down to the section about adding rope or jute with glue between the gaps, this might work? How you apply yours, Cubist? And where did you buy it from? I want to give it a go!

Also, a big question I have is, should I ideally add the gap filler after sanding and staining/varnish? I wasn’t planning on sanding til spring due to other jobs and just wanted to fill the gaps to cover us over the winter, but I’m not sure the order of doing things.

My other option is putting super thin matching wooden strips between the gaps. There are a few odd larger gaps, which makes sense to fill with wood strips, but most gaps are about 2-3mm? Is it doable to add wooden strips this super thin into the gaps?

How do I even get them that thin??

Here’s a photo example

 

[fernicarry]

Is it something like this on youtube

Similar concept but different process. I'm doing it from below with the boards in situ. I wouldn't attempt to lift old boards unless absolutely necessary as the survival rate will be very low. You'll also have issues where the boards run under internal walls.

The full build up is -- breather membrane in an inverted U stapled onto the underside of the floorboards and lapped down a short distance onto the joists and stapled again. Insulation pushed up between the joists, doesn't have to be very much, between 50 and 100mm. I use Indinature as it has the right balance of flexibility and stiffness. Another breather membrane below the insulation to prevent wind wash. Battens along the joists with OSB slats every foot or so for support. As I fix the battens I pull the lower membrane taught so that its in good contact with the underside of the insulation. The height of the battens is set so that the insulation is slightly compressed overall to keep it in intimate contact with the underside of the floor.

In places where I've removed skirting boards (usually to repair the plaster) then I bring the membrane up around the edge of the floorboards and fix it onto the wall with airtightness tape before reattaching the skirting board. Anywhere two elements meet each other there is the possibility of a draft so check all the joinery around your window reveals etc.

The economy version is to stop after the first step with just the membrane directly under the floorboards. This at least kills the drafts and gives you about 3/4 of the total benefit. The insulation is just the cherry on top as you don't lose that much heat downwards. I've only done small sections of insulation so far, mainly towards the outer walls where air movement is greater or under radiators where heat loss could be greater.

I don't expect condensation to be a problem because its all breathable and the objective of the build up is to avoid leaving void spaces that warm air could leak into.

 

[lizziecupcakes]

Similar concept but different process. I'm doing it from below with the boards in situ.

thanks for sharing! So, forgive me if I misunderstood, but do you mean you’re going under the house into the crawl space?

And do you mean I could trial breathable membrane just on the underside of the floorboards? That sounds like a good option, couples with @Cubist ’s rope solution for the gaps.

This is all so very interesting!

 

[Cubist]

Hi LCC.
Lots of questions here so I'll try to keep my responses brief... except perhaps for the first statement here: -

• DO NOT TRUST CHATGPT- despite my recent personal application for Ancient Monument status, my personal work history includes the design and development of computer based Expert Systems and Judgement Processors that, together with what is often referred to as Big Data, is the foundation of all the AI systems out there today. CHATGPT, and the rest, are only as good as the 'expert' data they use and are therefore subject still to the GIGO law of computing.
  • The lack of trust for Caulking Cotton you found was no doubt due to someone who didn't use it properly. Bad workmen always blame their tools OR the materials.
  • My status as a Human has been challenged many times and remains a subject of heated dispute in some quarters.
• Yes, Caulking Cotton was and is still used to make wooden boats/ships water-tight and it's safe to assume therefore that, when it's properly installed, it can easily block draughts.
• Rope and Jute were/are frequently used for the same purpose but care should be taken as the structure of some ropes severely limits their ability to be compressed and then expand to achieve a tight fit in some joints. Also, some materials used in modern ropes will resist dyes and other colouring agents to blend their final finish with the surrounding timber.
• I have added a section below dealing with where to buy and how to use Caulking Cotton.
• The wisest and most effective work sequence would be to Sand the Floor, Fill the Gaps, Apply Colour and then Apply the chosen Varnish/Laquer/Oil and Wax Final Finish.
  • Floor and Edge Sanders used by the pros are very powerful and can be heavy to use but are capable of covering large areas fairly quickly and can be hired from many outlets.
  • Power tools aimed at the private users are capable of doing the same job but these bring with them penalties in the shape of more time needed to do the job and a small in increase of the risk of damage.
  • BOTH though would be capable of destroying or simply ripping out ANY filler materials, including wooden strips, previously used to close the gaps.
• ALL this work is extremely messy and disruptive and at each stage there are risks that need to be understood and handled effectively.
  • While sanding, the house will be full of dust so it's wise to have some form of vacuum extraction equipment on hand and used throughout the process. Nevertheless you'll be finding the dust everywhere for months.
  • While filling the gaps between boards care must be exercised with any chemical fillers and glues as some of these can bleach or otherwise colour the immediate area of use, and/or prevent a dye/stain you intend to use later being absorbed into the wood, thus leaving unsightly and highly visible patches. Some of the 'finer' chemical fillers can, while its is being 'swept' into a gap can also be difficult to remove from low spots in the grain structure and further careful sanding will be needed to remove these unwanted patches.
  • Making, cutting and installing strips of a matching wood to fill a gap is: -
    • The single most difficult, time consuming, messy, frustrating and stultifyingly maddening techniques you can ever attempt and NEVER, EVER, UNDER ANY CIRCUMSTANCES over anything but the smallest or areas and only for gaps exceeding 4-5mm - anything less and you'll be booking a place in a Funny Farm.
      • Many of the pros will not even consider it unless they can see a big fat cheque at the end of the job.
• Your floorboards appear to be pine tongue and groove.
  • Unless the tongue was damaged or destroyed at some stage the gaps between the boards will not penetrate to the void below. Besides limiting the depth of the gaps to circa 10mm or less this also means that they would inhibit draughts getting through from the void and into the room.
  • It would be wise to check for the presence, or absence, of the tongue by using the edge of say a paint scraper to explore the depth of the gaps.

Now, about where to buy and how to use Caulking Cotton.

Caulking cotton is typically sold by weight and currently costs around £12-15 for 0.5 kilo and is mostly available from Boat Chandlers; I'll put a link to an example in the post later. Various diameters are available but the most common is around 8mm. This, when twisted and pulled, can be reduced to around 1 - 1.5 mm and even then can be compressed even further. Typical installation suggests it should be 'hammered' into place but that is really only necessary when you're aiming at a water-tight joint for a boat or say an external door frame. For internal use with those floorboards of yours a little muscle pressure under the edge of a suitable tool would be all that is required to press it into place. I've used Caulking Cotton to close any number of gaps around this place and these have ranged from anywhere between <1mm to 20+mm. For anything above 2-3mm it may be necessary to braid several strands together to form a rope of the required thickness. The Chandlers will suggest some fancy tools in the shape of a variety of what look like chisels but you can ignore these, an old dull bolster chisel, a wide blade stubby screwdriver and an Upholstery Tack Lifter are all I've ever needed - the latter is particularly useful.

The technique for installation that works best for me is to tie a knot in the loose end of the cotton and use this as anchor in the gap between boards just before a corner and then, while turning that corner, draw the cord toward you while twisting it between your fingers and firmly pressing it into the gap as you proceed along the seam. Turning the corner will also help maintain the anchor as you proceed and will help you avoid inadvertently pulling all the cord out or pulling it through along the length of the seam. The objective is for the cord to get a tight connection to the boards on each side as it tries to relax from the twisting and pulling actions. Personally I aim to find some resistance when I try to gently pull the cord out. Also, should you find that the gaps widens to a point where the cord becomes too loose, you can pull out the last few inches of cord, tie an additional cord to the the original just before the gap widens and braid them together to recover the tight fit.

Depending on your aims for the floor the cotton can be installed flush or a few mm below the final surface. I've found that a milk chocolate brown emulsion paint can be used to achieve a close match to old oak. This can deceive an observers eye and when finished with say a clear wax or lacquer look almost identical to the surrounding wood. Alternatively, if pushed down into the gap to a couple of mill, it can do an excellent job as a bed for any other filler you may use.

See link below.

8 Ply Best Caulking Cotton 1/2kg | Jackson Marine

Soft, top quality caulking cotton made up of eight strands totalling an uncompressed diameter of approximately 8mm. Used for the caulking and re-caulking of wooden carvel planked classic boats and new build wooden yachts. The caulking is often pushed in to place with a caulking iron, in turn...

www.jacksonmarine.co.uk

 

[fernicarry]

but do you mean you’re going under the house into the crawl space

Correct.

 

[Cubist]

I've added some pictures below of my use of Caulking Cotton indoors together with some comments. For the most part there was little purpose in my doing this as there was no risk of water or draught penetration however CC did prove very useful to block hidey-holes favoured by the ever present spider population. The first photo is of a gap that varies from 3mm to 1mm over its length and the second from 8mm to 5mm. The third starts at around 12mm and reduces to 0mm over 30cm and, due to a Chocolate Brown emulsion paint, is almost impossible to see from more than half a metre away.

Outdoors, all applications are invisible as they were subsequently coated with a lime render or filler but these included window and door frames and some of the rendered infill panels- which also stops the local bird population stealing the cotton for their nests.

 

[Cubist]

Oh, and as the above clearly demonstrates, I was never permitted to braid my daughters hair and am now excused those boots for my granddaughter too.

 

[mardinor]

I'd buy a big rug and cosy slippers, and enjoy the fresh air. You're in the wrong house for barefoot living and T-shirts year-round, but the right one for a sense of place and transcendence.

 

[lizziecupcakes]

I'd buy a big rug and cosy slippers, and enjoy the fresh air. You're in the wrong house for barefoot living and T-shirts year-round, but the right one for a sense of place and transcendence.

Yeh I know what you mean, but i think to some degree it’s possible to achieve something that isn’t freezing cold. I might be wrong though. I’m always in my nemo socks usually anyway haha