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How to build an external window frame?
Hi All,
A while ago my builder and I halted our renovations due to a lack of funds. We fitted a tall narrow stained glass window, which my Mum made, in between the timber frame (studs). Until now, I've just filled in the gap around the window frame with paper towels and packing tape on the outside to block the weather and insects.
So, I'd like to install a simple hardwood frame; could you please help me understand what to do here? What wood can I buy from Bunnings? I would just like to get a hardwood plank cut up and have the two sides plus the top and bottom screwed into place, painted and caulked. Do I put screws in through the external window frame to the studs as well as into the stained glass window frame, just the stained glass frame, or just the studs? Do I remove the chock once I have other sides screwed into place?
I will paint the raw cement sheet before installing the frame.
Thanks,
Jason
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Re: How to build an external window frame?
Well, we are halfway done...
I had to remove a 4m downpipe, add some Brutus cover trim, clean down and paint the undercoat on the raw fibro, then I caulked all around the window before working on the external frame.
We had some old timber from a door frame that I did a test run on for the 45º cuts, and the other half decided it worked well enough to stick with. So now all the gaps are covered until we get time to unscrew it, sand and paint it, then reinstall and caulk it. Hopefully that will happen on Tuesday.
Next thing I need to learn is how to fix broken fibro such as the hole at the top left of the window shown here. Also, those Brutus trim's bring a question to mind, as someone who lives in a 'bushfire prone zone' (thanks Council and insurance companies), I think that these will just melt and provide no benefit at all, am I right? My house really is a dogs breakfast, but I'm learning bit by bit and making improvements as I can afford to.
Thank you all for your help thus far
Jason
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Re: How to build an external window frame?
Hi Jason (@BoeingFan),
Nice work so far, those mitres look good.
I'm excited to see how it is once it is finished.
Thank you for the update.
Jacob
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Re: How to build an external wIndow frame?
G'day @EricL
I got my other half to pick up a click and collect order for me yesterday which contained a can of the Parfix 340g Expanding Foam Filler (though some mongrel had nicked the nozzle so I can't use it til I get back to town on Friday!) and I noticed on the back of the can it says 'extremely flammable'. I'm wondering if that is only until it cures, or even after it cures?
If it remains extremely flammable, is there another competing product such as Sika 500ml Boom Expanding Foam Filler less flammable? Living in a bush fire prone zone is a pain in the dairy air (another reason why I always use hardwood over pine).
Cheers,
Jason
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Re: How to build an external wIndow frame?
Hi @BoeingFan (Jason)
If you are after a fire-resistant expanding foam, I suggest using the Sika Boom Foam Expanding Fire Rated PU 750ml it is a 1-part, fire resistant, self-expanding polyurethane foam, which meets fire resistance requirements up to 180 minutes according to AS1530.4. Please note that this product will need to be specially ordered at the special orders desk and is subject to availability.
However, in regards to the regular expanding foam it is generally considered less flammable than when it's wet and curing, it's not entirely non-flammable. After curing, it becomes more fire-resistant, but it can still ignite under high heat or direct flame exposure. It would be best to cover it up with the timber trim for extra protection.
If you need further assistance, please let me know.
Eric
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Re: How to build an external wIndow frame?
G'day @EricL (Eric),
Thanks so much, that's an option I feel more comfortable with. I'm not far from finishing the window project, though I need to order a new fibro panel for delivery to wrap this project up (and a new front door whilst I'm at it) so I've ordered the fire rated Sika on eBay to arrive on Tuesday.
As always, I'm grateful for your help.
Thanks,
Jason
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Re: How to build an external wIndow frame?
Hi @BoeingFan (Jason)
Please make sure to post a photo of the window once you've placed the trim around it. I'm sure our members will be keen to see what it looks like.
Eric
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Re: How to build an external wIndow frame?
Good Evening @BoeingFan
Just as an option with that hole in the fibro, how about installing an extra piece of timber across teh top of the window, kind of like a header that overlaps the window both sides, covering the hole in the process? Silastic it as you install so the top and side is waterproof around the hole and you may get away not having to replace the fibro
Dave
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Re: How to build an external wIndow frame?
G'day @Dave-1 (Dave),
You've piqued my interest with that line of thought. From the bottom of the grey horizontal brutus fibro trim, to the bottom of the top horizontal window frame piece, it is 180mm. At minimum, I'd need a 500mm piece of wood to make it cover the fibro gap and be balanced across the top of the window. The challenge is that the fibro gap drops down below the top edge of the external frame...
I could glue a piece of timber using the construction adhesive to cover the remaining gap, and balance it on the other side. Alternatively, I could get a deeper (top to bottom, ie over 180mm) single piece of timber and cut out where the window frame is on the bottom side, to create a one piece addition. Much like a [ that is rotated clockwise 90º. The only other option we've thought of is to cut out another piece of fibro to match the gap and glue and nail it into place, then do the final frame caulk to make it water tight. What do you think?
I ordered from Starlink their $19 cable routing kit to make a nice neat cable route through the wall as well, which I'll need once this fibro gap is filled.
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Re: How to build an external wIndow frame?
Hi @BoeingFan
That cable routing kit looks great. I'm putting my vote to the extended piece of timber at the top. I also propose moving your internet cable below the window (close to the floor if possible) so that it does not interfere with the overall look of your window.
Eric
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Re: How to build an external wIndow frame?
Evening @BoeingFan
I agree with @EricL on moving the starlink cable if possible. And here is what I was meaning with the thicker timber trim added to the top and bottom of the window (to make it match) I was thinking Merbau, which comes in 90mm and I think 180mm? or 190mm? Its just as a cover overt the hole so nothing gets in. The small bit thats left, you could do what you were suggesting with a piece of fibro or use the Sika Foam that @EricL suggested.
The purple is merbau, probarly the 180mm ish thickness.
Dave

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