Hey all. I'm building a lean to extension with a low pitch 15 degree roof. Just coming to end of blockwork and adding wall plate. Just measuring to see how much space I have for roof. Does this sound OK -
So for a 15 degree pitch over a 3.4m span (to wallplate) the rise is 911mm. I have a total of 1200mm above wallplate to first floor window. So if I take off the 911, 200 for roof timber, 25 for battern and 50mm for tile this leaves me with 14mm to get lead in under windows!! Bit tight. Can I cut my birdsmouth into my timbers deeper to give me some space? I think I can cut into them by 1/3 is that correct. If so this would give me around 60mm more to play with and would be much better.
Thanks in advance
So for a 15 degree pitch over a 3.4m span (to wallplate) the rise is 911mm. I have a total of 1200mm above wallplate to first floor window. So if I take off the 911, 200 for roof timber, 25 for battern and 50mm for tile this leaves me with 14mm to get lead in under windows!! Bit tight. Can I cut my birdsmouth into my timbers deeper to give me some space? I think I can cut into them by 1/3 is that correct. If so this would give me around 60mm more to play with and would be much better.
Thanks in advance
