Thread: Roof timber and venting

Having had a bit of a poke up on the roof of the new house over the past few weekends, I've found a couple of things that need fixing.

First, timber. The wood that the tiles hook over in one spot isn't the same as the rest, nor is it fastened down. It looks like this was done after someone put the rangehood vent in.
What sort of timber do I need to buy to replace it with? I presume it needs to be treated?

Second, the extractor fan in the bathroom just blows straight into the roof. There isn't any vent above it to get it out of the roof space (I remember there was one in the rental I was in previously). Is there any cause for worry of all the steam getting shoved into the roof? Or should I go out and buy a whirlybird or something similar?
I live in WA if that helps at all.

Thanks in advance

Originally Posted by LordBug

Having had a bit of a poke up on the roof of the new house over the past few weekends, I've found a couple of things that need fixing.

First, timber. The wood that the tiles hook over in one spot isn't the same as the rest, nor is it fastened down. It looks like this was done after someone put the rangehood vent in.
What sort of timber do I need to buy to replace it with? I presume it needs to be treated?

You probably don't need to replace it - just screw or nail it to the trusses or rafters or even to other battens. It does not need to be treated although if the rest of your roof timbers are then it would be good practice to match the existing battens treated framing will be dyed blue or green and have printed markings of the relevant standard).

Originally Posted by LordBug

Second, the extractor fan in the bathroom just blows straight into the roof. There isn't any vent above it to get it out of the roof space (I remember there was one in the rental I was in previously). Is there any cause for worry of all the steam getting shoved into the roof? Or should I go out and buy a whirlybird or something similar?
I live in WA if that helps at all.

Thanks in advance

It is no longer allowed to vent directly into roof spaces, but might well have been when your house was constructed and that's what matters. In a climate as dry as most places in WA this will not be a problem - certainly not in Perth. If you are in a high humidity area then the answer would be to directly vent to the outside using a tube (usually galvanised iron, but can be plastic for bathrooms & ensuites) with a hat and a Dektite or similar to waterproof the hole through the roofing material - and this is how a new installation is done to comply with the Building Code of Australia (BCA).

IMO neither of the issues are all that much to be concerned about - in summary: a)make sure the batten is securely attached to the adjacent framework and b) enjoy your showers (which should be only 4 mins anyway ) and don't worry about the steam.

Originally Posted by oldbloss

You probably don't need to replace it - just screw or nail it to the trusses or rafters or even to other battens. It does not need to be treated although if the rest of your roof timbers are then it would be good practice to match the existing battens treated framing will be dyed blue or green and have printed markings of the relevant standard).

That's a relief. It's a bit thinner than the normal battens, and whoever put it in there put in two pieces to make up for it's extra flex, though I see that nailing it down will fix that.
All the other wood in the roof is just straight jarrah (Or showing how far my ignorance of roofing materials & wood in general goes, wood that looks like jarrah ) as far as I can see, no distinct colouration suggesting treatment that I can determine.

It is no longer allowed to vent directly into roof spaces, but might well have been when your house was constructed and that's what matters. In a climate as dry as most places in WA this will not be a problem - certainly not in Perth. If you are in a high humidity area then the answer would be to directly vent to the outside using a tube (usually galvanised iron, but can be plastic for bathrooms & ensuites) with a hat and a Dektite or similar to waterproof the hole through the roofing material - and this is how a new installation is done to comply with the Building Code of Australia (BCA).

Another relief, thanks

IMO neither of the issues are all that much to be concerned about - in summary: a)make sure the batten is securely attached to the adjacent framework and b) enjoy your showers (which should be only 4 mins anyway ) and don't worry about the steam.

Wish I could convince the missus to cut down on her showers, but I really enjoy having fingers


Just to throw another question in, I noticed on the weekend that there are horizontal cracks forming around the top of the walls in some rooms, just below the cornice. Looks like a case of the previous owners having painted over them to make the sale a bit easier.
The house is about 38 years old, so this shouldn't be a case of green timbers shrinking should it? (That's a problem that occured at the previous place, a rental. The resulting cracks were damn large, and the place wasn't even a decade old)

Thanks for your help

All house have cracks and especially at joins such as where cornice meets walls etc. Newer paints that are more flexible and stay that way for a while help hide them, but fact is mostly we have to live with them.

In a timber framed house they are mostly a function of varying humidity and changing temperature which causes almost continuous expansion and contraction - and because we use materials with different thermal properties and co-efficients of expansion that we try to fix them together solidly something has to give (in steel framed houses too, less so in double brick or block).

Unless they are bigger than a mm or two or keep expanding (which indicates continuous movement in one direction over time) then best to forget about them. If they are annoying then you can fill with a flexible acrylic or other filler and paint over (if you can match the colour).

BTW - I love jarrah, but as an easterner find it hard to adjust to it being used for house framing! Just fasten that piece you were concerned about an it should be fine.