Evening all. I've ended up doing this roof myself, main bits are all good but would really like some reassurance/advice on the ridge detail.
Scenario- box section sheets on top of 50 x 25 battens on top of rafters, 10 degree pitch. Rafter ends to be covered with 400mm capping board (the rafters are 300mm deep) on top of 300 x 20mm bargeboards (a lot cheaper than 400mm fascia boards, the ridge will be very difficult to access once the roof is on so I wanted the zero maintenance PVC rather than timber).
Question- should I set the capping board so the top of it is level with the top of the ridges on the box section sheets or should I set it so the box section sits on top of the capping board. At the moment I'm thinking sheets over the capping board so any water blown up the roof will tend to drop over the top of the fascia rather than behind it (though see Q3)
Question 2- I've got 125 x 175 steel ridge flashings to go over the ridge (and the gables). Which way round would give the best weather protection- 175 over the roof sheets & 125 dropping down the fascia or the other way round? Prevailing wind blows across the roof (door faces south, ridge is east, wind mostly comes from the north)
Question 3- again with these ridge flashings is it a good idea to fill the troughs of the sheets with expanding foam under the flashing (so windblown water can't get under the flashing)
Ta
Scenario- box section sheets on top of 50 x 25 battens on top of rafters, 10 degree pitch. Rafter ends to be covered with 400mm capping board (the rafters are 300mm deep) on top of 300 x 20mm bargeboards (a lot cheaper than 400mm fascia boards, the ridge will be very difficult to access once the roof is on so I wanted the zero maintenance PVC rather than timber).
Question- should I set the capping board so the top of it is level with the top of the ridges on the box section sheets or should I set it so the box section sits on top of the capping board. At the moment I'm thinking sheets over the capping board so any water blown up the roof will tend to drop over the top of the fascia rather than behind it (though see Q3)
Question 2- I've got 125 x 175 steel ridge flashings to go over the ridge (and the gables). Which way round would give the best weather protection- 175 over the roof sheets & 125 dropping down the fascia or the other way round? Prevailing wind blows across the roof (door faces south, ridge is east, wind mostly comes from the north)
Question 3- again with these ridge flashings is it a good idea to fill the troughs of the sheets with expanding foam under the flashing (so windblown water can't get under the flashing)
Ta
