Well, how do I answer that, I haven't exactly measured the temperature, but we've never experienced them as cold and walked around freezing. We have lived in the house for 6 years, when we moved in our youngest child was 3 months old, and he doesn't have any frostbite as far as I can seeAhlbom said:
. Where the floor was poorly insulated, there was modern oak parquet, further into the room was laminate. The laminate felt significantly colder than the varnished parquet. From that, I draw the conclusion for myself that with retained insulation and solid plank floors, the perceived floor temperature will be the same or better. The properties of the surface layer significantly affect the feeling of cold or warm floors. I have also noted that the windproofing must have fulfilled its function well, as it immediately started drawing up cold air from below when it was torn up.Our carpenter suggested using modern "windproof" in the joist spaces instead of the old black fragile paper. The modern crinkly tear-strong that most manufacturers have is easy to cram into all nooks and crannies and get sealed without tearing. I have used windproofing quite a bit on the rest of the house, and I understand what the carpenter means, it is convenient to handle in that way.
We have a tiled stove and wood stove that both run pretty much every day during cold seasons. Where the joist meets the foundation of the chimney, the thickness of the insulation was 0 cm. The foundation slopes down towards the ground, where the insulation increased, up to about 10 cm. Our foundation wall is made of flat natural stone that is plastered on the outside, so we have an apparently completely (wind)tight foundation wall. In the part of the house I'm talking about here, the foundation wall is 20-40 cm high on the outside.
We also have, like most people do, and as they used to, rugs in the walkways, and even under the sink. (Nice to stand on, and pleasant to wash woven rugs barefoot on summer vacation with soap and scrubbing brush on a tarp on the grass. Dry over a ladder lying between a couple of trestles.)
Now I have installed half of the floor joists, it became a combination solution to attach them to the outer wall. I cast pads at the height allowed by the outer wall stones that the beams rest on, then 90x90 mm angle iron is attached to the sill. The beams are 225 mm high, a bit of an odd measurement but it was the timber available at home. And some of the beams I had to cut/bevel down the edges to about 120 cm so they would reach the wall. The plan now is to lay asphalt paper/roofing felt the last bit out from the blind floor towards the sill and support it underneath with some battens so it doesn’t sag. In some cases, there will only be about 5 cm of insulation clearance over the stones, but I hope that will be sufficient as the rest of the floor is so well insulated.
A small update on this thread, a year later:
I haven't made any more progress since last time. Only now has the project gained momentum again, and next week I'm going to replace the damaged sills. But I've had time to think about how to solve this over the past year. It's heavily leaning towards pouring a slab in the entire house (or rather three slabs, one in each room). The idea is to fold the foam insulation up against the sill, creating an overlap of 10-30 mm. This will then be sealed tightly with age-resistant foam sealant. On top of the slab, a solid wood floor will be screwed. Aesthetically, this won't be noticeable, so I have no problem with this non-antiquarian solution, as long as it works. What do you think?
An additional thought, do mice eat foam insulation (which is exposed behind the retaining wall under the sill..)?
I haven't made any more progress since last time. Only now has the project gained momentum again, and next week I'm going to replace the damaged sills. But I've had time to think about how to solve this over the past year. It's heavily leaning towards pouring a slab in the entire house (or rather three slabs, one in each room). The idea is to fold the foam insulation up against the sill, creating an overlap of 10-30 mm. This will then be sealed tightly with age-resistant foam sealant. On top of the slab, a solid wood floor will be screwed. Aesthetically, this won't be noticeable, so I have no problem with this non-antiquarian solution, as long as it works. What do you think?
An additional thought, do mice eat foam insulation (which is exposed behind the retaining wall under the sill..)?
With us, there has been an earthen bank in the entrance hall and main room. In the chamber, a crawl space with a blind floor had been constructed on top of the old earthen bank. Not ventilated enough, of course, and inside, all the wood was in significantly worse condition. The sill was affected by rot, and unfortunately, the floor beams had to be replaced.
Well, after many long considerations, we've come to roughly the same conclusion you've been thinking about. We are digging away the sawdust they insulated with near the walls (directly on the ground!) and replacing it with 300-400 mm of lightweight expanded clay aggregate a meter in. Otherwise, we're leaving the foundation as it is; it will be ventilated with indoor air just like in our extension. Our builders want to insulate and have suggested polystyrene, but I (with support from Skansen's building conservation) don't want to destroy the moisture migration that has been allowed for 150 years. It might be a bit cold on the floor, but we'll probably manage with sheepskin slippers and the stove. We're considering casting a slab in the future bathroom... But that's something to think about a little more.
Well, after many long considerations, we've come to roughly the same conclusion you've been thinking about. We are digging away the sawdust they insulated with near the walls (directly on the ground!) and replacing it with 300-400 mm of lightweight expanded clay aggregate a meter in. Otherwise, we're leaving the foundation as it is; it will be ventilated with indoor air just like in our extension. Our builders want to insulate and have suggested polystyrene, but I (with support from Skansen's building conservation) don't want to destroy the moisture migration that has been allowed for 150 years. It might be a bit cold on the floor, but we'll probably manage with sheepskin slippers and the stove. We're considering casting a slab in the future bathroom... But that's something to think about a little more.
We have an unmortared stone foundation. The ground level inside is about thirty cm higher than the ground level outside, but the floor joists are not in the soil but just above it. Against the foundation wall, soil has been dug up and sawdust has been placed on top. This is where we plan to dig out and replace with Leca balls. The floor framework is completely free from the walls, on transverse logs that lie in the soil, and I recall that the sill is not in the soil (but can check with my husband to be sure). This is in the main room, which has the foundation that is dry, nice, and problem-free.
oh dear, hmm ... well ..jon_h said:
I can only say that I'm glad I've decided to build new instead ...
No offense meant, absolutely. It will surely be great when it's finished.
It's definitely wonderful that there are building conservators in our country, an unbeatable feeling to walk in and look around in a well-renovated old house.
Konichiwa girl: I understand. Sounds like a sensible solution.
Mikael: Hehe, yes.. It's actually completely dreadful when you stand and look at it. It's lucky that I have a very clear vision of how it's supposed to be. But the road there is terribly long, and longer it gets with every board you tear down and find more rot..
Mikael: Hehe, yes.. It's actually completely dreadful when you stand and look at it. It's lucky that I have a very clear vision of how it's supposed to be. But the road there is terribly long, and longer it gets with every board you tear down and find more rot..
I'm considering whether it might be better to use concrete blocks as a border around the slab, instead of folding up the foam insulation? It might result in slightly lower insulation capacity, but on the other hand, the mice won't have a chance to gnaw their way in.
That's roughly how it was done in one of the wings at my girlfriend's uncle's place.jon_h said:My second idea, which I would like to get some comments on, is to dig out properly, maybe lay 50 mm washed macadam, new floor structure on leca blocks and attach it to the walls, and then fill up to the top of the joists with leca balls 12-20K, which are capillary breaking at 75 mm. The total layer with leca balls might be around 2-300 mm.
Comments on this or other ideas would be greatly appreciated.
The inner floor, however, became completely floating from the outer walls if I remember correctly. What the floor was on I can't remember either, maybe leca blocks. But then all the space underneath was filled with leca balls.
Whether this solution is good I am not the one to answer. I don't think the uncle can give feedback either since it was probably the craftsmen who chose it, obviously in consultation though, I would think.
The uncle is also one of those hopeless people who can't imagine dealing with houses from the 1900s. This is from the 1700s something ...
I think you can largely disregard the insulation capability, because you're probably not planning on underfloor heating, right?jon_h said:
The concrete blocks have about the same insulation capability as the wooden logs, approximately. So if logs work just fine right above, then...
I'm unsure about how well concrete blocks absorb ground moisture capillarily, how well and quickly they dry out compared to the foam insulation.
Concrete blocks certainly have better long-term properties than foam insulation. Maybe not entirely unimportant in a house that should stand for another 200 years... at least...
If I understand your construction correctly, you lack a foundation wall. But there are foundation stones here and there, on which the walls rest?
Some of the problem remains if I choose such a construction. I still have to seal the few centimeters where the beam structure overlaps the sill. So, maybe you still have to place a leca stone edge (foamed against the sill?) and then set beams and fill inside them. And then I wonder if it’s not better with a slab anyway, then you avoid the moisture-sensitive beams.Mikael_L said: