Hi ya,
I just want to sound this out with other experienced Carpenters. I have a customer that would like a velux put into the roof above their kitchen and for the void in the loft to be boxed in forming a sun tunnel through the kitchen ceiling.
The property is a Bungalow the roof is a gable with a pitch of about 20 degrees, inside the loft there are two purlins 9x4 either side as you would expect with low level collars, the purlins are supported via struts which connect to the joist binders which along with the purlin run front to back of house.
In order to install the velux it would be necessary to cut approximately one metre out of the purlin and the binder to form the sun tunnel. I can form new struts to the binders* from the purlin at the point they have been cut. I can introduce a second binder as close to the sun tunnel stud work in the roof eve and tie the joists back together and I can introduce new collars either side of the cut out in the purlin.
Its supporting the Purlin that concerns me, cutting through the binder will mean that both cuts will be unsupported other than sitting on joists which are 4x2 as the sun tunnel will be in the centre of the kitchen ceiling. I suppose I could introduce two 9x2 C24 joists sitting on the centre load bearing wall to the wall plate and strut the purlin to these, bolting the binders to it aswell?
Or do I advise that they need a structural engineer?
I just want to sound this out with other experienced Carpenters. I have a customer that would like a velux put into the roof above their kitchen and for the void in the loft to be boxed in forming a sun tunnel through the kitchen ceiling.
The property is a Bungalow the roof is a gable with a pitch of about 20 degrees, inside the loft there are two purlins 9x4 either side as you would expect with low level collars, the purlins are supported via struts which connect to the joist binders which along with the purlin run front to back of house.
In order to install the velux it would be necessary to cut approximately one metre out of the purlin and the binder to form the sun tunnel. I can form new struts to the binders* from the purlin at the point they have been cut. I can introduce a second binder as close to the sun tunnel stud work in the roof eve and tie the joists back together and I can introduce new collars either side of the cut out in the purlin.
Its supporting the Purlin that concerns me, cutting through the binder will mean that both cuts will be unsupported other than sitting on joists which are 4x2 as the sun tunnel will be in the centre of the kitchen ceiling. I suppose I could introduce two 9x2 C24 joists sitting on the centre load bearing wall to the wall plate and strut the purlin to these, bolting the binders to it aswell?
Or do I advise that they need a structural engineer?
