It's going to be about installing a new floor in the house with a timber frame, so I thought I'd ask how to do it 
I plan to use 45x220 and frame with cc300 if you want tiles because the span is up to 4.6 meters.
The idea is to attach a board/rule around the log wall at the right floor height to create a box and then frame it with cc300.
How do I attach the joists in this "box" to the board fixed on the wall? Do I screw in at an angle from both directions, how many screws, and what dimension should the screws be?
Or should I use some sort of joist hangers? That would be quite a few in that case...
Ideally, you'd want to screw from the backside right through the board along the wall and straight into the bearing board, but that's a bit difficult.
I plan to use 45x220 and frame with cc300 if you want tiles because the span is up to 4.6 meters.
The idea is to attach a board/rule around the log wall at the right floor height to create a box and then frame it with cc300.
How do I attach the joists in this "box" to the board fixed on the wall? Do I screw in at an angle from both directions, how many screws, and what dimension should the screws be?
Or should I use some sort of joist hangers? That would be quite a few in that case...
Ideally, you'd want to screw from the backside right through the board along the wall and straight into the bearing board, but that's a bit difficult.
Joist hangers provide a stable attachment. Use ones that are adapted to your lumber dimension.
With a CC of just 300mm, you'll need a lot of joists.
What will you have on top (under the tiles) have you thought?
One or two noggins across the beams also stiffen the construction.
With a CC of just 300mm, you'll need a lot of joists.
What will you have on top (under the tiles) have you thought?
One or two noggins across the beams also stiffen the construction.
so it's joist hangers that are required then? I didn't actually think that... then maybe it will be this one... 12:-
http://www.byggmax.se/spik-och-skruv/byggbeslag/balksko-p235097
yes, a lot of joists are needed... there is a previous thread where I ask how best to construct the new floor and there "we" concluded that it will be cc300 approximately... depending on whether I should have a bottom sheet, the cc measurement is calculated on half the width of the sheet...
on top of the joists, I will have slatted panels with underfloor heating pipes + plates
on the slatted panel, I will have a layer of floor gypsum to help spread the heat,
Where tiles will be laid there will be an additional screwed glued layer of floor gypsum
I will also have blocking, 2 where the span is large and 1 where the span is about 3 meters.
I will also cast a couple of plinths, partly because the rooms are not rectangular but have a fireplace in the corner, and there you probably have to frame around it in some way and there will be a cast plinth in the inner corner or whatever you want to call it.
where the span is large, I also plan to cast a couple of plinths directly under the joists and then block from the plinth to thus bind the framework together.
possibly one would cast plinths and lay a support beam, e.g., 2 pieces of 145*45, in the rooms that are a bit larger, about 4.5x4.6 meters each in the kitchen and living room. but that reduces the space to crawl in the foundation later...
http://www.byggmax.se/spik-och-skruv/byggbeslag/balksko-p235097
yes, a lot of joists are needed... there is a previous thread where I ask how best to construct the new floor and there "we" concluded that it will be cc300 approximately... depending on whether I should have a bottom sheet, the cc measurement is calculated on half the width of the sheet...
on top of the joists, I will have slatted panels with underfloor heating pipes + plates
on the slatted panel, I will have a layer of floor gypsum to help spread the heat,
Where tiles will be laid there will be an additional screwed glued layer of floor gypsum
I will also have blocking, 2 where the span is large and 1 where the span is about 3 meters.
I will also cast a couple of plinths, partly because the rooms are not rectangular but have a fireplace in the corner, and there you probably have to frame around it in some way and there will be a cast plinth in the inner corner or whatever you want to call it.
where the span is large, I also plan to cast a couple of plinths directly under the joists and then block from the plinth to thus bind the framework together.
possibly one would cast plinths and lay a support beam, e.g., 2 pieces of 145*45, in the rooms that are a bit larger, about 4.5x4.6 meters each in the kitchen and living room. but that reduces the space to crawl in the foundation later...
No, you need stronger/higher joist hangers for the dimension you specify. Ex. 45x197 mm (Not available at ByggMax..)
If you're going to install underfloor heating, be sure to strictly follow an installation method as specified by the manufacturer (very carefully).
If you're going to install underfloor heating, be sure to strictly follow an installation method as specified by the manufacturer (very carefully).
There are 45x168 at Biltema but I'll look around a bit more and maybe find something affordable...GoForIt said:
but do I really have to use joist hangers?
My underfloor heating supplier recommends doing as the tile seller suggests
they recommend at least a sparse panel and then parquet, but for tiles they had no recommendation...I would appreciate comments on my other questions about plinths... it might be hard to understand what I mean... I can take pictures tonight of what the rooms look like
Best regards
okay can someone explain this calculation for me?
http://www.traguiden.se/TGtemplates/popup1spalt.aspx?id=826
it seems they are using a joist hanger 45x137 for joist 45*220, the one sold at byggmax
http://www.byggmax.se/spik-och-skruv/byggbeslag/balksko-p235137#ReadMore
but it should surely be nailed/screwed in a special way... anyone know?
http://www.traguiden.se/TGtemplates/popup1spalt.aspx?id=826
it seems they are using a joist hanger 45x137 for joist 45*220, the one sold at byggmax
http://www.byggmax.se/spik-och-skruv/byggbeslag/balksko-p235137#ReadMore
but it should surely be nailed/screwed in a special way... anyone know?
I can't quite understand how you were thinking of attaching them otherwise, given the conditions you describe (of course, it's a bit difficult when you can't see it physically on site).
I was involved in a retrofit of underfloor heating in a joist space a few years ago, where the manufacturer's instructions weren't followed to the letter, and the end result wasn't fun at all.
What kind of underfloor heating are you planning to install? Surely there must be detailed instructions on how it should be done?
Feel free to take some pictures as you suggest. It's easier to understand then.
I was involved in a retrofit of underfloor heating in a joist space a few years ago, where the manufacturer's instructions weren't followed to the letter, and the end result wasn't fun at all.
What kind of underfloor heating are you planning to install? Surely there must be detailed instructions on how it should be done?
Feel free to take some pictures as you suggest. It's easier to understand then.
I can see several alternatives to joist hangers.
The same "frame" where you would have attached the joist hangers, you instead screw-glue a 45x45 timber at the bottom. On this timber, you then place your floor joists. Toe-screw them into the frame. To compensate for the floor joists being 45mm too high compared to the frame, you can place an additional 45x45 on top of your "frame." This only works if there is room for a 265mm high floor system. One advantage of this is that you (to further reinforce the floor) can screw-glue a 45x95 to the bottom side of your floor joists. This will act as a tension flange and thus create a significantly stronger floor system. Be sure to use glue carefully and screw relatively closely. Another advantage is that you can lay the subfloor boards directly on this "tension flange."
If there isn't room, you can instead notch each floor joist 45x45 at the bottom, in this way, you can still use the 45x45 timber as a bearing instead of joist hangers. But this alternative risks taking longer than using joist hangers.
The same "frame" where you would have attached the joist hangers, you instead screw-glue a 45x45 timber at the bottom. On this timber, you then place your floor joists. Toe-screw them into the frame. To compensate for the floor joists being 45mm too high compared to the frame, you can place an additional 45x45 on top of your "frame." This only works if there is room for a 265mm high floor system. One advantage of this is that you (to further reinforce the floor) can screw-glue a 45x95 to the bottom side of your floor joists. This will act as a tension flange and thus create a significantly stronger floor system. Be sure to use glue carefully and screw relatively closely. Another advantage is that you can lay the subfloor boards directly on this "tension flange."
If there isn't room, you can instead notch each floor joist 45x45 at the bottom, in this way, you can still use the 45x45 timber as a bearing instead of joist hangers. But this alternative risks taking longer than using joist hangers.
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Joists on cc60, 22mm chipboard flooring, and 12mm self-leveling compound are also okay for tiles. It's much more fun to handle when insulating, running pipes, etc. It's tighter than you think to work at 25.5cm.
Try getting a regular drill with a flat bit down there...
Try getting a regular drill with a flat bit down there...
sure, but I also need to fit the underfloor heating with a 20mm pipe,,, grooved floor chipboards are insanely expensive.JOW said:
if you self-level, the cost unfortunately runs away,
good input regarding the space for, e.g., drilling, but it becomes 27.5 cm for me if you consider that the subfloor boards are 55cm and you divide them in the middle and put studs based on them. I'm considering using tongue and groove as the subfloor, and then you could have a wider spacing like cc400, which might be more advantageous in all respects.
Great suggestion! 45x45 costs only about 6:- per meter so it will be significantly cheaper than beam hangers. There is space down into the crawl space, it's just a matter of digging a little deepervectrex said:
but the foundation stones are a bit irregular so special solutions need to be made at each stone.Regarding the "tension flange," I've been thinking of using 22x95 or similar to have something to lay the subfloor on. Is it much stronger to use 45x95? Perhaps you could even manage with fewer or no concrete pillars if you do it this way?
One thing I've been considering, however, is that I would only like to screw this underlying plank if you ever need to access the insulation from below... then it's relatively easy to unscrew these and remove the subfloor... if you've glue-screwed, it becomes virtually impossible.
It's 20 mm waterborne, intended to be laid in a spaced panel with underfloor heating plates.GoForIt said:
In what way wasn't it good where the manufacturer's instructions weren't followed?
I will take pictures when I get home and upload them, will try to photograph in a 360-degree series so you can see everything
I will also need to build a new foundation wall on the western side, but that will be a new thread with pictures
For example, if you look in the VVS manual from Uponor, there are several different installation options where it is described in detail how to do it. There must be a similar one from the supplier you have chosen as well.thestrut said:it's 20 mm waterborne, intended to be laid in spaced panel with underfloor heating plates
in what way was it not good where they didn't follow the manufacturer's instructions?
I will take pictures when I get home and upload them, I will try to take a 360-degree series so you can see everything
I will also need to make a new foundation wall on the western side, but that will be a new thread with pictures in it
In the case I described, they used exactly the method (underfloor heating plates in spaced panel) you describe, even though it turned out to be assessed as "less suitable" in the specific case. The result was an uneven floor with sway, where the tile joints did not hold and tiles came loose.
If you just have a crawl space underneath, you have all the possibilities to make strong solutions that give building height.
I have read that... and it's not recommended with tiles...GoForIt said:
I THINK my solution will be very stable actually. and I have discussed this in other threads here on the forum and it should work according to other forum gods
cc30 45x220 + 22x70 sparse panel + 2 layers of screwed glued floor gypsum. possibly going up to 28x70 sparse panel
what can happen is that the grout cracks, since it's not a wet room you can regrout...
it's also not quite decided with my partner what floor covering we'll have, it might just be 1 layer of floor gypsum and parquet on this, then you can later if you want switch to another layer of gypsum and tiles, in case you would change your mind...
I've kind of gotten stuck on floor gypsum since it helps to spread the heat MUCH better than floor chipboard from what I've read at least
in the case you describe, did they have cc300 with 45x220 or stronger, as well as 2 layers of screwed glued floor gypsum on the sparse?
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What I have written is that I recommend you follow the advice given by the underfloor heating manufacturer, but ultimately, that's for you to decide.
Why start another thread if you are completely sure about how to construct the floor?
I rest my case.
Why start another thread if you are completely sure about how to construct the floor?
Yes, if you build on that premise, most things will work.thestrut said:
I rest my case.