Hi,
I live in a single-story house with a basement built in 1946, with an area of about 70+70 sqm. We are planning to start renovating the basement in the next few months to get more rooms to use. But there are a few considerations that come up.
If you want to change walls, how do you know which ones might be load-bearing? Is it necessary to build new walls with masonry in the basement, or can you use a wood construction? I have read about drywall against the outer wall, so I have a handle on that.
Then I'm thinking about the floor, is it worth tearing up the old floor to insulate and possibly lay underfloor heating?
About how much would such a project cost, without the underfloor heating? What should you fill with, and how much does it build in height, do you think?
Those who have renovated, please share good tips, ideas, and preferably pictures for inspiration so we can finally get started.
Thank you in advance.
Best regards,
Jonas
I live in a single-story house with a basement built in 1946, with an area of about 70+70 sqm. We are planning to start renovating the basement in the next few months to get more rooms to use. But there are a few considerations that come up.
If you want to change walls, how do you know which ones might be load-bearing? Is it necessary to build new walls with masonry in the basement, or can you use a wood construction? I have read about drywall against the outer wall, so I have a handle on that.
Then I'm thinking about the floor, is it worth tearing up the old floor to insulate and possibly lay underfloor heating?
About how much would such a project cost, without the underfloor heating? What should you fill with, and how much does it build in height, do you think?
Those who have renovated, please share good tips, ideas, and preferably pictures for inspiration so we can finally get started.
Thank you in advance.
Best regards,
Jonas
We have a house from 1943 with 76 sqm + 76 sqm basement.
For us, this means kitchen, living room, bedroom, and toilet on the ground floor.
We have a laundry room, bathroom, boiler room, and future computer/gaming room.
Not exactly professionals on load-bearing walls, but for us, they are continuous. So, the walls go from the basement up to the ground floor. Almost all our walls, in other words
We have chosen to have as little organic material in the basement as possible and have therefore used steel studs and Minerit boards where we needed to frame something.
Our walls are plastered. Very nice.
For us, this means kitchen, living room, bedroom, and toilet on the ground floor.
We have a laundry room, bathroom, boiler room, and future computer/gaming room.
Not exactly professionals on load-bearing walls, but for us, they are continuous. So, the walls go from the basement up to the ground floor. Almost all our walls, in other words
We have chosen to have as little organic material in the basement as possible and have therefore used steel studs and Minerit boards where we needed to frame something.
Our walls are plastered. Very nice.
If the basement was originally built with masonry, it should probably remain that way. Wooden structures in old basements are not a good idea. Whether it's worth jackhammering the floors and installing underfloor heating is difficult to answer. It involves a lot of work, so it's either expensive or requires a lot of hard work on your part. You should dig down almost half a meter and then create a capillary-breaking layer in the form of gravel. It's advisable to have a geotextile layer at the bottom. This prevents moisture from rising to the new warm floors. Then insulate with at least 30 cm of foam insulation. After that, pour new concrete with the underfloor heating in it. Use tubing if you have water-heated floors or electric coils if you prefer electric heating. The house will have good thermal comfort if the entire basement is done. I don't think you should insulate the basement from the inside. It is much better to do it from the outside with Isodrän or equivalent. There are plenty of threads here on the forum with pictures if you search a bit for basement renovation or similar. Go for it!
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Determining which walls are load-bearing is difficult without seeing a blueprint. My own house (-43) is quite elongated (about 6.5 x 10.5 m) and it has a clear "heart wall" that divides the basement, right in the middle lengthwise. There is then a corresponding heart wall above on the living floor, so in my case, it's simple - don't touch the longitudinal heart wall, everything else I can basically tear down if I want.
However, I have an acquaintance who lives in an almost square house, where the basement is "squared" so to speak; a central chimney stack and then load-bearing walls in each cardinal direction, dividing the basement into four main parts.
- I agree with everyone above about avoiding organic material in the basement.
- If you need to redo drainage, it's a good opportunity to insulate the basement from the outside.
- Check the condition of water and sewer pipes. If you anyway have to chisel up the basement floor to replace pipes, you might as well chisel up the ENTIRE floor, insulate it, and install underfloor heating at the same time (or vice versa; if you plan to chisel up the floor anyway, seize the opportunity to replace the pipes!)
- Excavating the basement is not particularly complicated, but it takes effort and time. Rent or buy a good demolition hammer. The worst part, I think, is getting all the material out; hauling it up stairs is not recommended, but it's possible to rent conveyors and get it out through basement windows or something similar. Luckily, I had a basement door directly out, so it was just about pushing a wheelbarrow. But it takes many trips!
Of course, you can buy labor too; since it's labor-intensive it's an efficient use of the ROT deduction.
Costs are hard to answer, as you might understand I've done most of the work myself; chiseled away around 40 sqm of the basement floor (dug out about 35 cm in total), replaced all drains, laid ground fabric, gravel, radon suction pipe, foam insulation, cast a new floor with waterborne underfloor heating, and laid tiles. The most expensive items were underfloor heating (around 15,000) and the tiles (around 25,000). The only experts I hired were for the connection and pressure testing of the underfloor heating system and concrete pumping for the floor.
However, I have an acquaintance who lives in an almost square house, where the basement is "squared" so to speak; a central chimney stack and then load-bearing walls in each cardinal direction, dividing the basement into four main parts.
- I agree with everyone above about avoiding organic material in the basement.
- If you need to redo drainage, it's a good opportunity to insulate the basement from the outside.
- Check the condition of water and sewer pipes. If you anyway have to chisel up the basement floor to replace pipes, you might as well chisel up the ENTIRE floor, insulate it, and install underfloor heating at the same time (or vice versa; if you plan to chisel up the floor anyway, seize the opportunity to replace the pipes!)
- Excavating the basement is not particularly complicated, but it takes effort and time. Rent or buy a good demolition hammer. The worst part, I think, is getting all the material out; hauling it up stairs is not recommended, but it's possible to rent conveyors and get it out through basement windows or something similar. Luckily, I had a basement door directly out, so it was just about pushing a wheelbarrow. But it takes many trips!
Of course, you can buy labor too; since it's labor-intensive it's an efficient use of the ROT deduction.
Costs are hard to answer, as you might understand I've done most of the work myself; chiseled away around 40 sqm of the basement floor (dug out about 35 cm in total), replaced all drains, laid ground fabric, gravel, radon suction pipe, foam insulation, cast a new floor with waterborne underfloor heating, and laid tiles. The most expensive items were underfloor heating (around 15,000) and the tiles (around 25,000). The only experts I hired were for the connection and pressure testing of the underfloor heating system and concrete pumping for the floor.
Worth it? Depends on how you calculate it.
Yes, it is definitely worth breaking up the basement floor and installing underfloor heating as far as I see it. I’ve installed waterborne heating in about half of the basement where we live and shower.
But speaking in terms of comfort, economically it’s more doubtful, likely costs more than just paying for the heating as it is today.
In a basement like you describe, I would never use wood or other organic materials; there are alternatives, so there’s no reason to take a chance on that.
We also replaced the plumbing while we were breaking and removing concrete chunks, a damn messy job but worth the effort once it was done.
I don’t have much idea about the cost, but we always do as much as possible ourselves, then you KNOW it’s done properly and it becomes cheaper even after ROT.
Yes, it is definitely worth breaking up the basement floor and installing underfloor heating as far as I see it. I’ve installed waterborne heating in about half of the basement where we live and shower.
But speaking in terms of comfort, economically it’s more doubtful, likely costs more than just paying for the heating as it is today.
In a basement like you describe, I would never use wood or other organic materials; there are alternatives, so there’s no reason to take a chance on that.
We also replaced the plumbing while we were breaking and removing concrete chunks, a damn messy job but worth the effort once it was done.
I don’t have much idea about the cost, but we always do as much as possible ourselves, then you KNOW it’s done properly and it becomes cheaper even after ROT.