I would be grateful for some solutions on a problem a friend has with a garage roof of a property she is about to buy from her father's estate. The garage is one side of a pair of semi-detached garages measuring 5.3m x 3.2m (5.3 x 6.4 for both) where both sides have severely pooling; with the neighbours being the worst. At present there are no leaks.
The pool of water extends from about a metre at the high end for almost the entire remainder of the roof length and about 300mm from the side and party walls. So the puddle is about 4.5m x 2.5m (elliptical). Internally the roof has sagged about 35mm at its lowest point.
It seems the 400mm centered joists, which run side to side (approx 6.4 metres) through the party wall are way under size at 100mm and the firrings, which run front to back are 50mm at the high end to nothing at the low end over a length of approx 5.5 metres (which I think gives a fall of 1:110 at best).
The roof covering is green mineral felt (not sure of its weight but I don't think it the heavier 35 or 38Kg) topped with about 10mm of additional granite chippings, which are full of moss and algae. After heavy rain the weight on the presumably weak roof must be a lot.
The neighbour has been approached but does not seem that interested stating "the roof timbers and felt were only replace about 12-13 years ago". Which probably means its due for a new covering soon anyway. Having said that, a large shed on the property has a roof cover of the same felt, without additional granite chippings, and that seems sound with no visible signs of deterioration.
My friend would like to replace the roof with a tiled pitched one but the neighbour was absolutely against that due to the high cost.
So my questions are:
Any help would be much appreciated.
The pool of water extends from about a metre at the high end for almost the entire remainder of the roof length and about 300mm from the side and party walls. So the puddle is about 4.5m x 2.5m (elliptical). Internally the roof has sagged about 35mm at its lowest point.
It seems the 400mm centered joists, which run side to side (approx 6.4 metres) through the party wall are way under size at 100mm and the firrings, which run front to back are 50mm at the high end to nothing at the low end over a length of approx 5.5 metres (which I think gives a fall of 1:110 at best).
The roof covering is green mineral felt (not sure of its weight but I don't think it the heavier 35 or 38Kg) topped with about 10mm of additional granite chippings, which are full of moss and algae. After heavy rain the weight on the presumably weak roof must be a lot.
The neighbour has been approached but does not seem that interested stating "the roof timbers and felt were only replace about 12-13 years ago". Which probably means its due for a new covering soon anyway. Having said that, a large shed on the property has a roof cover of the same felt, without additional granite chippings, and that seems sound with no visible signs of deterioration.
My friend would like to replace the roof with a tiled pitched one but the neighbour was absolutely against that due to the high cost.
So my questions are:
- What can be done if the neighbour will not play ball and have the entire roof replaced.
- What is a reasonable cost (in north Hampshire) to replace the flat roof with a tiled pitched one probably with plastic clad gable ends. My friend would consider paying the cost for both sides if the neighbour would contribute half the cost of an entire new flat roof.
- To keep the costs of a pitched roof down could the existing joists be reused given that they are likely to be bowed (max deflection of worst joist 35mm)? The gables ends would be front and back so would be parallel with the existing joists.
Any help would be much appreciated.
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