Replacing a suspended floor (insulation)

[platypus]

So now I've done the job I thought I'd share some pics.

From this:


To this:


Via....


It took a day to get the old floor entirely up. I didn't originally plan to get rid of the fireplace, but it just seemed like a good idea once I'd gone this far, as I was unlikely to have an opportunity again.


It took an awful long time to clean up as well!


I had to replace one of the main joists:


and two in the corner where the air brick was completely blocked:


Here's a decent image showing how I worked the netting/insulation:


Given that I've cut through gas pipes before, I was particularly proud of this brain wave:


And here's the temporary boxing I put in over the fireplace:


We're getting carpet fitted soon, so hopefully this will help that, and then when we find a hearth/mantel we like I'll install that.

 

[Felix]

I was looking at doing the same but from below. My main concern is dry rot, so should a vapour membrane or barrier be used etc.

I was going to go for the earthwool option.

 

[platypus]

I think I've decided against a vapour membrane. It's far more important to make sure that the space under the floor is properly ventilated (eg via air bricks).

 

[eidolon]

I'm planning on doing pretty much the same so I'd also be interested in what people recommend.

 

[platypus]

Ok well looks like I'll be the guinea pig for you two guys. I'll let you know how I get on!

I've decided to use 50mm bats, for the simple reason that my joists are not regular widths, and the bats are easier to cut (imo).

 

[Felix]

Doing a search on the net, there is a split between PIR, Batts or rolls. PIR being the most expensive but most effective. Batts can be held in place with battons (as with PIR) but could sag if not completely supported. Rolls of earthwool being the cheapest though.

 

[platypus]

Yep my plan will be to batton it at regular intervals. I just think with my dodgily spaced joists batts will make measuring things much easier.

 

[platypus]

Ok well this went pretty well I thought. I'll post some pics up when I get them sorted.

Quick one off my phone though, sort of just under halfway:
.

I was really quite pleased to find out that there was virtually no damp. The air bricks were all blocked up with dirt and dust, but other than that in good shape. The slate course was also in great shape, so now that I've cleaned out most of the dirt from there and replaced the floor, I'm confident that going forwards the ventilation will be just fine.

I bought a heavy duty plastic safety barrier roll for £18, and simply sat the insulation on top of that after stapling it to the joists. This also worked out really well, with getting insulation that was the depths of the joists, so it just sits flush with the boards.


(you can just about see the netting in the bottom right corner).

The old floor was completely dry rotted through. Fortunately though, this really hadn't transfered to the joists in a big way at all. I had to replace two joists, and brace a few others, but the majority were actually in good condition. Still, I treated them just in case, and just because I had the opportunity too.

As I'd gotten rid of the old fireplace I boxed it in with a temporary job (for carpet fitting), until we find a mantel piece we like, and make a decision on whether to put a stove in or not.

 

[Showboat]

Looks like great fun!
Make sure you take plenty of pictures

 

[Mark A]

Nice work, should be a lot warmer with that insulation in there.

Are there air bricks in the external wall to allow ventilation?

 

[platypus]

There are indeed. They were almost completely all blocked up with dirt, sawdust, and brick dust however. Cleaned them out so the ventilation underneath should be absolutely fine now. There was virtually no damp whatsoever, just a tiny bit in the far corner next to one air brick that was completely and utterly blocked. The slate line is good all thr way round, and I've adjusted some joists that I didn't replace so that there is a gap between brick and joist. I'm really confident that the floor will be in excellent condition now for many a year.

I'll get round to posting proper pics this weekend.

 

[Simon]

Nice- that's the way I would have done it too

 

[Buffman]

Looks good!

Couple Qs;

• Is the floor panelling your new replacement for floorboards? (Is it a suitable replacement??) I used something similar in my loft.
• Shouldnt you take the skirting board off prior so that your skirting sits ontop of your skirting board?
• How did you staple the vapour barrier under the floorboards? (did you have to climb underneath?)

Unfortunately I've already sealed most the floors in my home, that and it's a bit of a utilities nightmare, with (old/disused) ventilation ductwork, gas pipes, and heating pipes going thru

 

[platypus]

Update the op with pics!

Looks good!

Couple Qs;

• Is the floor panelling your new replacement for floorboards? (Is it a suitable replacement??) I used something similar in my loft.
• Shouldnt you take the skirting board off prior so that your skirting sits ontop of your skirting board?
• How did you staple the vapour barrier under the floorboards? (did you have to climb underneath?)

Yep I used the chipboard to save time. We've got a 10 month old, and with the amount of dirt/crap this job creates he had to be out of the house, so I only had a long weekend to get it done. As the joists were so close together it was fine to use.

Ideally yes you'd take the skirting board off, but again to save time I didn't bother. In most places, I was able to knock the panels under the skirting anyway - I bought the same depth panels as the old floorboards so in most cases this was absolutely fine. I had to leave a 2cm gap in one alcove, but as I'll be building in cupboards this won't matter.

Stapled it the hard way - on my back! I did 99% of the floor, leaving a small gap to get out, and then stabled a bit over the last hole just to the side of the joists.

 

[Simon]

Nice job

 

[Felix]

Good work, any reason why you went for orange site barrier rather than netting? I presume just for the strength?

Pleased to see I am not the only one to use Hetty for building work!

 

[platypus]

Good work, any reason why you went for orange site barrier rather than netting? I presume just for the strength?

I just wanted something that wouldn't sag, to keep the insulation pressed up tight against the boards. I felt that the heavy duty barrier would work better than netting. I could well be wrong on this point, but it was only £17.99 so I thought it worth the money.

Pleased to see I am not the only one to use Hetty for building work!

She's brilliant! Fills up quickly with all the brick/sawdust and dirt though, I think if I were starting afresh and had to buy a vacuum I'd get a Titan like my father in law has. It's no better at suction than a Henry/Hetty but it takes 25 litres so you don't need to empty it anywhere near as often.

 

[Felix]

I just wanted something that wouldn't sag, to keep the insulation pressed up tight against the boards. I felt that the heavy duty barrier would work better than netting. I could well be wrong on this point, but it was only £17.99 so I thought it worth the money.

She's brilliant! Fills up quickly with all the brick/sawdust and dirt though, I think if I were starting afresh and had to buy a vacuum I'd get a Titan like my father in law has. It's no better at suction than a Henry/Hetty but it takes 25 litres so you don't need to empty it anywhere near as often.

Where did you manage to get the barrier from? I've got to work from underneath, attaching one side of netting, stuffing earthwool in and then attaching other side of netting. So wondering if that barrier would be better.

As regards Hetty, I actually bought the smaller Titan and found the build quality was rubbish and a short hose.

 

[platypus]

https://www.amazon.co.uk/gp/product/B00K1ZNPM4/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1 - I think its ok to link because OcUK don't sell safety barrier. It's gone up £2 but still a good deal.