Drain holes in DIY window

[itsmatt]

I'm looking to fit double glazed units in place of old single glazing we have either side of our patio doors. The frames are thick timber and I have absolutely bags of depth to play with so figure this should work just as long as I can get the internal beading true!

I've watched various videos about dry fitting and so I understand the process of using tape and spacers. Everyone mentions the need to leave a drainage space below the unit but I'm not sure what the best way to let that drain would be in this case.

I'm going to add a cill in place of the current beading so should I just router/chisel a couple of slim channels in the base of the frame that will run underneath my hardwood cill per the sketch (marked 1 and 2)?

Any pointers gladly received!

 

[cdbe]

I have dg units in my 1930s timber frames, they're just puttied in. I always thought the drainage in plastic frames was for water that got past the rubbers seals?

 

[itsmatt]

I have dg units in my 1930s timber frames, they're just puttied in. I always thought the drainage in plastic frames was for water that got past the rubbers seals?

I see, yeah - were they in casements or fixed frames? I was just planning to use the dry fit method per this guy's vid where he uses the security tape, spacers and outer beading. Feels like it'll be a more forgiving approach in terms of position and size tolerance – though annoyingly, he mentions he's taking steps to ensure drainage at the bottom but he never comes back to elaborate! Most other videos I can find that mention drainage at all seem to all be about UPVCs.

TBH our plan is to fully replace the entire arrangement at some point in the future so perhaps it's a case of trying it out and keeping an eye on it as a learning experience.

 

[Mr Chibs]

Will you need drain holes if you move to double glazed units with wooden frames, not sure you will.

You get condensation galore when you have single glazing, which you shouldn't get with DG.

Some experts will comment, but as you've a generous frame depth, you could get a large gap between both panes when you have the DG panels made, think this increases the thermal properties.

 

[itsmatt]

Will you need drain holes if you move to double glazed units with wooden frames, not sure you will.

You get condensation galore when you have single glazing, which you shouldn't get with DG.

Some experts will comment, but as you've a generous frame depth, you could get a large gap between both panes when you have the DG panels made, think this increases the thermal properties.

Hmm - had never thought about water ingress from the inside. I'd been assuming it was primarily about rainwater eventually working its way in.

These windows are in a kitchen-diner on the north side of the house so I'd be surprised if we get away without condensation altogether - although I do still hope it'll be much reduced!

I think I'm going to press ahead - I'll try and remember to check back in down the line to report my findings!