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4 replies
non-"openable" wooden decking on roof terrace?
We are planning to install a "deck" on our flat roof terrace. (There is living space under the deck and folded sheet metal under the wooden decking).
We are thinking of using Massaranduba wood, which is very heavy, and are now considering whether it would work to screw the planks into a frame that is not openable. This way, we can lay full lengths and avoid dividing the decking into small sections that can be lifted.
What do you think about doing it this way? A lot of dirt/leaves, etc., accumulate over the years under the decking...
We are thinking of using Massaranduba wood, which is very heavy, and are now considering whether it would work to screw the planks into a frame that is not openable. This way, we can lay full lengths and avoid dividing the decking into small sections that can be lifted.
What do you think about doing it this way? A lot of dirt/leaves, etc., accumulate over the years under the decking...
I assume you're going to have decking with gaps?
If you drop something, how will you retrieve it if you can't lift the decking?
The worst isn't that you get leaves under the decking, but what they can cause in the long term. Especially spruce and pine needles are aggressive against metal. Even treated ones.
As you describe the base, I guess it's metal sheet covering with wide strips of metal and a seam that's double folded (double seam) in the direction of the roof slope?
Perhaps standing or knocked down?
What is the slope of the base?
What total build height can you afford by the wall?
How thick is the decking material?
These are answers needed to be able to give you exact advice on what you can and can't do.
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The Builder
If you drop something, how will you retrieve it if you can't lift the decking?
The worst isn't that you get leaves under the decking, but what they can cause in the long term. Especially spruce and pine needles are aggressive against metal. Even treated ones.
As you describe the base, I guess it's metal sheet covering with wide strips of metal and a seam that's double folded (double seam) in the direction of the roof slope?
Perhaps standing or knocked down?
What is the slope of the base?
What total build height can you afford by the wall?
How thick is the decking material?
These are answers needed to be able to give you exact advice on what you can and can't do.
____________________________
The Builder
The gap will be quite small since massaranduba doesn't expand much.
Aggressive towards sheet metal - yes, that doesn't sound great. Although there are no conifer trees in close proximity, the needles might travel a bit in the air...
The sheet metal covering will be with wide strips of sheet metal and a seam that is double-folded (double wrap) in the direction of the roof slope, just as you assumed. The decking wood is 25 mm.
Upright or downward? -> Which do you think is best?
What slope does the base have? -> We can control that. What do you think is needed?
What building height can you afford in total by the wall? -> We can also control that - your opinions are gratefully received.
Regards Melie
Aggressive towards sheet metal - yes, that doesn't sound great. Although there are no conifer trees in close proximity, the needles might travel a bit in the air...
The sheet metal covering will be with wide strips of sheet metal and a seam that is double-folded (double wrap) in the direction of the roof slope, just as you assumed. The decking wood is 25 mm.
Upright or downward? -> Which do you think is best?
What slope does the base have? -> We can control that. What do you think is needed?
What building height can you afford in total by the wall? -> We can also control that - your opinions are gratefully received.
Regards Melie
Then the framing needs to be at most 600 mm in cc-distance.Melie said:
Upright is best. Then the cover doesn't 'tie up' during down-dropping if done a little carelessly.Melie said:
For seam roofing with sheet metal and double coverage in the seam, at least a 3-degree slope is recommended.Melie said:
You should start from the bottom edge of the door out onto the terrace and account for 'creep' for the door in relation to how much snow may settle there. That is, less than 50 mm you cannot have below the bottom edge of the door leaf and what is below that. And I assume you don't want a stair out to the terrace? It might still be good to have a level that is max 180 mm higher than the terrace floor for that reason. That is, a step height. If you then make the step at least 295 mm wide, you haven't exceeded your ability to take a step and be down on the terrace floor afterward. If you want a wider platform, add 630 mm to the 295 to manage it in two steps with 180 in height.Melie said:
Addition:
Depending on the length of the terrace perpendicular to the slope direction, you could lay whole boards in that direction, but only a few on a removable deck. About 300 mm in width might be appropriate. Then you need to place loose joists along the slope direction (which can also be picked up) that are wedged on the underside and horizontal on the top side to lay the decking planks on. It's enough that you fasten them at the top of each end in the last and first deck board with a screw that can easily be unscrewed when you need to remove the innermost and last decking. Others can be lifted individually.
Another thing you should keep in mind is the ventilation under the roof that is seam-covered. It may be possible to have a ventilation gap along three sides, but against the wall, it is missing. There, you should try to arrange some kind of exhaust with a 'metal chimney' in some places that are drawn above the expected snow depth so that you do not get moisture into the roof. Alternatively, create an air box inside by the wall according to the same principle as a Dorade vent on a boat.
______________________
Builder
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