External reveal. How to make underneath of lintel look OK?

[EllaGnu]

Hello.

I'm building an extension with fair faced brickwork. The windows are set back 3.5" from the external face. A catnic type steel lintel supports brick soldiers on the outside skin.

My problem is how to make the underneath of the catnic look ok. I could paint it white (same as the window), but its going to look a bit naff. Someone suggested fixing gauze to it an rendering but this seems fiddly and prone to failure. Has anyone any experience of other ways to make the underneath of steel lintels look acceptable?

Thanks.

 

[noseall]

What sort of windows are you fitting?

Why are they set so far back?

I do like to see windows positioned back far enough so that there is little risk of cold bridge from the external masonry, but 3.5" is a heck of a lot.

 

[EllaGnu]

I've just had a look at the drawings and the architect has specified half a brick, or 100mm... even deeper than 3.5"!

He's done this is to match most of the existing windows. The windows being fitted are wooden flush casement. They will bridge the 100mm cavity but these are already closed with insulated cavity closers.

 

[noseall]

Has he specified a reveal fixing system because all there will be to fix to in the cavity is a lot of fresh air?

 

[EllaGnu]

The guy making the windows uses stiff metal straps that fix to the internal reveal (and are then rendered over).

 

[noseall]

The guy making the windows uses stiff metal straps that fix to the internal reveal (and are then rendered over).

Yes I know the type. They have a wee bit of movement/adjustment i.e. they swivel up or down. I would locate the window so that there is enough lap onto the external leaf to get a good seal against the masonry jamb.

Does this mean extra deep sills or are you fitting stone fellas?

Can you not fix a header timber fillet to deal with the top reveal or paint it the same colour as the window?

 

[EllaGnu]

Yes I was intending to recess them roughly 90mm to ensure a good seal with outer brickwork. The thermal bridging aspect is still a worry though.

I can use a wooden fillet (how to fix it though?) but am not too sure how the edge will look (and then add in the edge of the catnic too...)? Paint might be simplest but I was hoping for some way to make it look a bit better than that.

 

[noseall]

You are over thinking a small detail. Paint will be ok. Once you have other details to worry about this one will likely pale in comparison.

 

[seasickstevie]

Better painting it 'brick' colour, rather than white.

 

[EllaGnu]

Thanks. I am inclined to paint then brick colour (terracotta?) or black I think.

I'm perplexed by thermal bridging and don't know whether I should consider it an issue or not. As I said we are using insulated cavity closures but it seems to be that the windows bridge the cavity but worse still, so does the steel lintel! Won't this lead to condensation?

 

[freddiemercurystwin]

Too much over thinking going on here! Your Catnic will have some polystyrene in it, reducing the bridge to a minimum.

Its impossible to build a house with no thermal bridges. Just have to minimize them where possible.

The hiding the lintel issue has come up before a few times, sure I posted a few suggestions back then, can't find it now though, may have a better look later.

Of the top of my head they can be painted as mentioned or I think Catnic do a plastic cover for them that you slip over. Though not sure they look much better.

 

[themiddleagedun]

Like Jagger sang "paint 'em black" (or just leave them)

 

[tony1851]

Like Jagger sang "paint 'em black"

Careful there - you're showing your age