sealing timber purlins

[edgadav]

I have taken down the ceiling upstairs in my house and insulated and plasterboarded on to the rafters and left the purlins exposed. They have a small amount of woodworm on them but not alot, and i am wanting to keep them as natural looking as possible. Any ideas or suggestions as to what is best to treat and seal them with?

 

[catlad]

Linseed oil can bring the colour out of wood if you sand them down, have you made any alternative arrangement for taking your ceilings down?

 

[edgadav]

what do you mean by alternative arrangement?

 

[catlad]

Well normally the ceiling is part of the roof structure and to remove it is to weaken it.

 

[edgadav]

No the ceiling was not connected to roof at all. There is just 2 purlins supporting the rafters and the ceiling was old 3x2 riddled with woodworm and almost falling down which is why we took it down with intention to replace but then saw it without ceiling and decided to leave it as it was. Is that ok for you??

 

[catlad]

Well I am limited to what your tell me, but if you are telling me that the old ceiling was not attached to the rafter feet or the wall plate then it would be unusual.

 

[oldbutnotdead]

I think what our experienced catlad is pointing out is that your old joists, if they were running across the house, would have been helping to stop the roof spreading (by linking the ends of the rafters or the top of the walls together). Of course you may be playing in a place like mine where the joists ran the other way (parallel with the purlins).

From a structural point of view you might want something to link the 2 sides together- some joists or some tension bars would work.

The other trap is ventilation for the roof timbers.....

As for treating the worm, would have been best to do it before you boarded out- if you can see them in the purlins they're probably in the rafters as well. 5 gallon drum of Cuprinol, a Killaspray and a good facemask would do the job- you can brush the stuff on but it gets very boring.