Hi,
(TFP v16)
I have 2 layers Ground and First. The roof is part of the ground floor as it is tied to the walls there.
Problem is that various internal walls on the First floor level do no extend correctly (or at all). Main dormers are OK as these are fixed height walls and I did a manual roof cutout for these.
I tried moving the roof to the First floor level but I end up with a roof floating in mid air and cannot bring it down, even setting the support level to 0mm
What did I do wrong?
Cheers :)
Tim
Hi Tim,
Your roof must be on the first floor but you need to go to Building Locations and change the Wall Height to just a few mm or 1 inch. The roof will then sit at this height and the tiny walls will extend into the roof space.
Use the forum Search for Attic and you will find more details if you need them.
Allan
Hi Allan,
OK - Gotcha! I will go and try that and see how it goes :)
Many many thanks,
Tim
Hi,
Sorry - I did follow the method in some of the posts thrown up by the Search for "Attic".
One new problem:
My bungalow has cavity walls. The inner leaf is 2.4m high. The outer leaf is about 4 courses of bricks less.
The roof is steep at 40 degrees pitch (hipped).
As you can see from the screenshot, the walls from Ground level cut through the roof slightly - this would happen in reality if inner and outer leaf were 2.4m high, as the roof fascias sit low (at about 1.9-2m off the ground).
Of course the ground floor walls cannot be auto-extended to the roof as the roof is in the next higher location.
I also had to make the floor height for the first floor location artificially low so the roof would sit down low enough - even with 1mm walls.
I'm sure I've done something completely wrong but I cannot see it.
Any guidance would be most appreciated :)
I've attached a test project file too -
Kind regards,
Tim
Hi Tim,
The problem basically is in your location settings.
The Ground floor walls extend from the floor surface to the BOTTOM of the first floor floor (2438mm). You have a first floor thickness of 292mm, so the Floor Level for the First Floor (the floor SURFACE) should be 2730 (2438+292). If you determine what the floor thickness should be (292 is the default I think) and add this to the wall height, it will give you the Floor Level of the First Floor. Change that in the Location settings and the First Floor (and roof) will left and the protruding walls will disappear.
Allan
Hi Allan,
Thanks very much for that.
I see the problem. In reality the ground floor walls extend to the ground floor ceiling which is at 2.4m from ground.
The first floor joists (8"/200mm) sit on top of the 2.4m wall.
The ground floor ceiling is 25mm thick (double plasterboard) and hangs lower than the wall.
There is 20mm of first floor boards on top of the joists. So that's a floor segment about 245mm thick.
Let me try something...
Hi Tim,
You are getting the hang of it but still a couple of issues. The Floor Level setting is measured from the ground or Terrain level which is zero. So in determining the Floor Level you also have to take the thickness of the Ground Floor into account also - I should have mentioned this in the previous post.
The Floor Level is the top surface of the floor, whether it is solid concrete, tiles or timber boards on a timber frame. The Walls sit on top of this surface and the floor above sits on top of the wall. The first floor walls sit on this floor and the roof sits on the first floor walls. The ceiling sits at whatever height you want above the floor it is on and the height is calculated to it's under surface. Only the Floor Level (surface) is calculated from the Terrain (zero).
Hopefully that clarifies it a little.
Allan
Ah - thanks Allan.
I'm going to plot this out on a bit of paper and measure the gutterboard heights and overhangs properly in a minute.
I have a feeling that I *may* have to manually construct the cavity wall from 2 single brick walls too - the inner leaf is the load bearing on and the outer is not and is some 30-40cm shorter. If the roof is in a different layer to the GF walls, I suspect slipping (auto extend) will not work.
Hi Tim,
Two parallel walls will probably not work. They will probably meld together and, if not, you will have all sorts of issues with windows and doors not cutting through both.
I do not see what is concerning you. The ground floor walls will not extend to the roof - only to the bottom of the floor above them. Your upper level walls will have a 'drop face' that must be set to the floor thickness so it will cover the edge of the floor. The upper level wall itself will be only 1mm high, on the outside, but will be 30 or 40 on the inside depending on th slope of the roof - the program will do that all automatically.
Allan
Hi Allan,
The problem is rather the reverse:
My GF ceiling joists (also FF floor joists) sit directly on the inner leaf wall at 2.480m from GF level.
The roof rafters also sit on this leaf at 2.480m above GF level with a birdsmouth of about 25mm.
The only way I can get the roof right is to set FF thickness to be zero, "pigmy" FF walls of 1mm high, then the roof fascia hangs down to 2.1m off the GF level. You see the problem - my roof "sits down" quite low - 355mm below internal GF ceiling height
If I set my GF walls to 315mm thick, and 2.455m high plus the 25mm FF wall on top (reality) then the outer edge of the GF walls do indeed punch through the roof surface - and autoextend will not work as it's in a different layer.
Unfortunately the "drop leaf" will not work directly as we are already sitting the roof at the zero line of the first floor.
Essentially, TFP seems to make some assumptions that my building breaks.
I have one idea - which is to set the GF wall height at 2.1m and "drop leaf" the upper walls by 0.355m or so. It's a hack but I cannot see another approach.
I can use "elevate" to manually reset the floors and ceilings as necessary.
Would a side plan drawing help explain that?
Cheers,
Tim
Oh - that's weird...
I was going to try my idea. Reopened TFP and then the test drawing and the walls no longer clip through the roof???
Seems to have corrected itself on save/reload. I am confused, but I'll try redrawing my house properly based on this structure as the dimensions seem to be pretty much correct...
Thanks for the suggestions :) The floor thickness was a big help - I misread the little diagram twice - but if you look really hard it is the case as you say that the walls are measured off the floor - which I find a weird way fo thinking about building measurements!
Cheers
Tim
Hi Tim,
Sounds as though you are getting there!
Measuring the wall height from the floor appears logical to me - but I am not a builder! You need to bear in mind also that TFP is all about visualisation, so it is not necessarily concerned about internal (hence not visible) construction methods although it generally handles these logically also.
Let us know how it goes.
Allan
Yep - probably because I have spent quite a long time inside the structure - I know all the engineering (or lack of it!).
Best bit was when the roof tiles were off last month - standing on the scaffold at foot level with the attic spaces all opened up was very weird!
Cheers,
Tim
Here it is:
http://www.flickr.com/photos/74840865@N07/8231497909/ (http://www.flickr.com/photos/74840865@N07/8231497909/)
Thanks for all your help Allan.
Here's the result done correctly.
Basically, I set floor thicknesses to zero - it avoids unnecessary complications. I can float (I think) floors where I want them, ditto ceilings.
Cheers
Tim