Insulation and draughts

I can feel draughts but struggle to work out where they’re emanating from.

We had some engineered oak laid a few years ago - 2 of the rooms did not have solid floors but were carpetted - I suspect a lot of draught is coming between the gap from the flooring and skirting board which varies from negligible to maybe 5-6mm - older carpets were often dirty at this perimeter point suggesting air coming in from below.

Am about to order some foam (Draughtex or similar) to stick in the gap between skirting and flooring assuming it’ll be less messy than caulk or other filler if expansion effects cause the latter to crumble.

Next, the attic - old Victorian house - ancient rockwool type insulation between the beams, the very old itchy stuff, and so much surface dust/dirt in there generally - I’ve been tempted to get rid of it all for years and just want to get a protective covering on, dispose of old insulation and hoover the lot and replace with modern stuff, hopefully less of a physical irritant.

Would you just leave the ancient base layer and top up or get rid of all and replace with new - suspect I could do it DIY but perhaps more cost effective to get a professional to do so?

worth tracking the draughts down - candle works if you are careful…

some walls and spaces need the draught to stay dry but you want it to not come into the room, at least not too much.

Attic - nightmare to get that out, but if you did so you’d get more and better insulation in so it wuld be warmer. But if dry and no rodents around, I’d be tempted to cover it with more modern stuff, and maybe board over top to make it more usable and stop the itchy fibres. Ok to do yourself but can be nasty on the skin…

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Re loft insulation, most cost effective is definitely DIY - but ideally get one of those all-in-one disposable coveralls including hood, be sure to wear gloves, decent dust mask and goggles (I’ve got a full face mask type respirator from which is great, apart from copious sweating!). At least this time of year attics are cooler -I did my present house in summer, and it is a very cramped loft as well. I managed to get all my loft cheap when British Gas was sponsoring insulation 9 or 10 years ago, at about 1/10th of normal local store prices.

But cleanest and easiest is engage someone else, though making absolutely clear that you don’t want fibreglass or mineral wool fibres spread around the house.

Maybe estimate the amount you’d need and check current cost of buying, and contact two or three places for prices to undertake for you, then you can decide if the difference in cost to save the hassle is worth it, or better put towards your next hifi upgrade? DIYing almost everything is how I could afford to buy much of my hifi over tge decades.

If you’re in England, the government has a new grant scheme valid for a further 5 months paying 2/3rds of cost up to £5k, but for loft insulation that is only if none, or for top up to the current reCommended minimum - last time I looked that was 270mm of fibreglass. (I put About 450mm in mine.)

As for draughts around floors, I think foam, as in foam rubber, would difficult to put in place. Expanding foam difficult to get only where you want unless large gaps to fill. I used mastic, IIRC not silicone but more one of the ‘caulking’ products that in my experience shrink over time. I sealed any gaps between floorboards, and both along the bottom and top edges of skirting boards. No draughts! (i also cut trapdors in floorboards To get below the suspended floor and fitted 100mm of foil faced polyurethane foam boards (‘Kingspan’ clone) between the joists (actually 2x 50mm because it was cheaper and easier to handle). A bit tight in some parts of house where the gap underneath was only just enough to wriggle through!

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Removing the old stuff is really messy and you’ll have a huge pile of horrible dusty stuff to take to the dump, where it will likely be sent to landfill. I would leave it and put more on top, run at right angles to the old strips. It’s probably the most cost effective form of house insulation there is. Use a really thick layer (or two) and remember to seal the loft hatch very tightly, or the heat will simply rise through it and bypass the insulation.

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Yes, I forgot to mention that: attach 150mm of ‘Kingspan’ type insulation to the back of it: I used 3 layers of 50mm other brand glued together and glued to it, and rubber draughtseal around the periphery.

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Older houses need good ventilation, be careful you don’t create damp issues. If you have open fires or log burners extensive draught-proofing will have an effect on those too.

Our home is about 250yrs old. Draughts are part of the fun. When we first bought it there was not a jot of loft insulation and no roofing felt. You could see the stars through parts of the roof. Something we sorted pretty early.

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Thanks for the helpful responses all.

Assuming I muster up the enthusiasm to do the loft myself - any opinions on the best (or least irritant) insulation type?

Think I saw some a few years ago that were ‘sealed’ in a plastic like bag - more expensive but less likely to lose fibres. Not convinced they’d lay as well though.

I used the recycled plastic one from B+Q. Not the cheapest though, so worth looking around if its a large area

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Interesting one, thanks - possibly on the expensive side due to the overall area but I have considered only topping up over some of the colder areas especially as some parts of the loft are not as easily accessible as others.

I wonder what the R value of all the empty boxes and stuff I have stored up there is!

There are loose pellets that can be used for hard to reach areas. They can be poured then shifted around with a broom or similar. We used some in a very shallow and awkward space and with a bit of fiddling got decent coverage.

Discussion of merits and demerits of Micafil at website here. Not perhaps ideal for the whole space but they have a role

Bruce

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Interesting stuff - when we had the log burners installed the dividing bricks between the chimney flues had collapsed and we had to have some interlocking tubular channels (forget the names) placed in order to accomodate the flue liners. They used some kind of vermiculite/cement mixture to fix them in place from memory.

Yes, the potential for damp is a consideration. The front lounge has airbricks and a suspended floor, the adjacent hallway is a solid tiled floor. A channel connects the lounge diagonally with a suspended floor at the rear, whereas the area behind the lounge is solid floored.

Are these regions designed to ventilate/allow air in when there would have been numerous coal fires, or are they more to allow below floor moisture a route of escape.

When some of these area were carpetted the edges discoloured I assume due to dusty air coming from below but we rarely felt any draught.

Yes to log burners - 5kW and 8kW rated.

Rockwool in a plastic covering reduces breathability. I would just get the cheapest, thickest rockwool you can find. The worst of the hazardous stuff will be in the old insulation, not the new, so I would suggest a Tyvek suit, gloves and P3 face mask.
I would avoid loose fill insulation in a draughty loft, the wind can blow it all over the place!

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Good tips, thanks. I’d still love to get rid of the old stuff which is likely 30+ years old, very dusty, and probably soiled by birds that manged to get in and possibly mice. :flushed:

I did remove the old stuff from our loft before replacing it about 15 years ago. It was a very unpleasant job, and the nastiest stuff is the fine debris left behind after the rockwool rolls are removed. A vacuum cleaner took care of that.
Get yourself lots of large bin liners. I had just installed a couple of Velux windows in our loft, so chucking the old stuff out of the window saved squeezing it through the loft hatch and carrying it out through the house.

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Reminds me of our builders a few years ago who essentially chucked anything that didn;t need to stay out of a bedroom window - was less than impressed when they did so with glass :frowning:

if you do get rid of it, use a commercial or industrial vacuum if you can- I have a cheap yellow Karcher one for the garage - it’s basic but everything goes in. If you use a standard domestic one, it’ll likely clog too often…

It’s more environmentally friendly to leave it in place - up there it helps with insulation, anywhere else and it’ll just be landfill…

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I kind of agree with you on the enviromental aspect but it is horrible stuff and I’m not sure I’d want newer stuff contaminated with the old especially if we ever come do a loft conversion (then it may be sealed away I suppose). I have an old vacuum cleaner which should work ok and has several replaceable filters but again I appreciate your point - I’ve had a ‘clean’ and ‘dirty’ vacuum for some time for different tasks.

I reluctantly removed the old stuff from ours as it was badly broken down, and no longer filled the space between the joists. I’ve got an old Henry that did the job of removing the fine debris, complete with dust, mouse droppings, dead insects etc. I would have preferred to avoid dumping it, but it was doing a poor job of insulating, so it had to go.

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Re general house ventilation, install whole house heat-recovery ventilation: No damp, no stale smells, no worries with draught proofing (and no need for those awful “trickle ventilators” commonly fitted to uPVC windows to compensate for the original non-airtight ones.

An open fireplace is a significant heat loss feature unless suitably blocked - and when in use requires sufficient external ventilation to the room. (Best approach to that that I have seen was a vent installed behind a central heating radiator, so the incoming air was warmed somewhat before reaching occupants.) Infinitely better in my view if you want a real fire is a stove - and you can get them room sealed, with an under-grate air intake from outside the house, or in the one I installed in my last house the intake was from under the suspended floor.

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