New window openings @ 1st floor level

[Richard C]

I’m about to form 2 x 1200mm wide openings in a gable end wall for some new, windows. I’ve done some groundwork &, being an engineer, fully understand the need to support everything above while you get the lintel in place (pinning the walls & props etc.).

Problem is this is fine at ground floor level where it’s easy to support from both the inside & outside but can anyone advise what tricks to use to support the outside at first floor level? Is it acceptable to prop from scaffolding? Or is there some other trick my inexperience doesn’t know about!

 

[masona]

Have you follow the building regulations because of fire spreading from the window?

 

[Richard C]

Have you follow the building regulations because of fire spreading from the window?

Eh, sorry don't follow your drift. Have full planning permission & mostly understand the building regs.; it’s the experience of doing it I lack! The existing windows are in two separate rooms &, due to a crap 1960’s architect, currently overlook an overgrown hedge & someone else’s bathroom rather than looking out onto our fantastic garden; so I am installing two new DG windows & bricking up the old ones.

 

[DAZB]

For the size of opening ( 1200mm ) that you are fitting I would say that propping from the scaffold would be fine . It may be advisable to fit a few extra ledgers and maybe double up the boards under the props if you do just to be on the safe side. I once saw someone bolt together two Acrow Props through the holes on the foot plates to reach higher but it was with a 6ft and a 4ft prop and he braced it to a scaffold to be safe but I don't suggest you rush out and try that approach.
Failing that try some Skyhooks .!!

 

[masona]

Have full planning permission

Ahh, didn't know that Can't remember the details regarding measurement from the window to neighbour wall for preventing fire spreading, I think it was no less than 2m. I has to use glass blocks instead because it was less than 2m.

Is it acceptable to prop from scaffolding?

You can but explain to the scaffolder what you're going to do, normally they put a modular scaffold section across to take the weight and also brace the side to prevent tipping over.

 

[Richard C]

Thanks for the response; it seems I will have to prop from the scaffolding but I must say I am not that keen. I was trying to work out a way of rigging up some form of cantilever support from the inside, a bit like the side lift jack on a car, but am not convinced this would work. A builder I spoke to said with an opening of only 1.2m he would prop on the inside only & chance it but I’m not keen on that idea either. Maybe I’ll have a look on E Bay to see if I can pick up some second hand sky hooks!!

The neighbour wall issue is not a problem, it’s a detached property with black sheep & geese one side & the nearest neighbour the other side is over 25m away.

 

[masona]

I've not seen your job but normally not a lot of weight to support because the way the brickworks all tied in. As a example, if you took a a few bricks out it should not fall down in theory.

 

[Richard C]

I've not seen your job but normally not a lot of weight to support because the way the brickworks all tied in. As a example, if you took a a few bricks out it should not fall down in theory.

So, do you reakon I would get away with it? Have you done it before?
Nice tail rider quote by the way; Also Essex is where I've just gone from!

 

[masona]

I've not seen your job but normally not a lot of weight to support because the way the brickworks all tied in. As a example, if you took a a few bricks out it should not fall down in theory.

So, do you reakon I would get away with it? Have you done it before?

Rule number 1,

Never take a gamble, always prop it up safetly for a piece of mind plus we cannot see what you're doing. Always think about ahead as "what if?"

Spend more time preparing than the job, I have seen job go wrong when cutting corner.

I was giving you an example if you took a few bricks out, the brick around hold it together so in theory the support is not taking the whole weight of the house but you must still support it whatever.
Good luck.

 

[Monsoon]

Resurrecting this post as It's a similar job to mine.

Wasn't the answer to supporting his window opening from one side to use 'Strongboys'?

 

[Richard C]

Resurrecting this post as It's a similar job to mine.

Wasn't the answer to supporting his window opening from one side to use 'Strongboys'?

In the end we didn’t use anything (wait for it!). I decide to bring in a builder in the end & the guy had far more experience than me & said that the worse that would happen would be to loose one or two bricks from the top row. As he was fully insured, I let him get on with it; not even a crack appeared inside or out!

I would stress that although my openings were in a gable end, they were at 1st floor level & were only 1200mm wide apiece. The size of the opening you are knocking out does have a bearing on what’s likely to happen & they also went gently, gently drilling out most of the mortar around the outside before making the opening; if you knock 7 bells out of the structure with a thumping great kango or a 28 lb sledge hammer it’s obviously going to dislodge things to a greater extent, including all the internal plaster!

 

[Monsoon]

Good to hear all went well. I will be using strongboys on a ground floor opening - see my previous post:-
//www.diynot.com/forums/viewtopic.php?t=52831

The first floor opening will be similar in size to yours. The walls are supporting joists for a flat roof. Not a huge weight I would think.

The guy doing my building regs approval is a construction type (not arty designer type) so I will take guidance from him aswell.

Did it take long to complete your job?

 

[Richard C]

Did it take long to complete your job?

It took around a day to complete each window (opening) with lintel installed & make good but most of the time was taken up by the softly, softly approach of drilling out the mortar & internal blockwork so you don’t have to bash things too much! Fitting the window & sealing is about an hours work next day when the cement has gone off.

Strangely, I have just today cut another window in an existing wall based on the confidence gained on the first two windows & it all went well with no surprises (it’s bloody hard work though); considering you post, that’s a little bit eerie don’t you think!

Should have looked at your post first; Your pic looks very much like my extension at the moment except I currently have 4 acrows up & there is a panoramic view of our garden though the totally open front wall; but this bloody weather is killing me! but it's only single story so thre i sno real load!

 

[Monsoon]

Did it take long to complete your job?

It took around a day to complete each window (opening) with lintel installed & make good but most of the time was taken up by the softly, softly approach of drilling out the mortar & internal blockwork so you don’t have to bash things too much! Fitting the window & sealing is about an hours work next day when the cement has gone off.

Interesting they cut the hole on the same day. I was going to prop mine, cut and bed the lintel in. Leave it a few days to set and then cut the hole for the window.

I've got six openings to make, so by the time the mortar for the lintels has dried out I'll be ready to start slicing holes in the wall with the wall saw I'm hiring from HSS.

I spoke to my building surveyor and told him my plan to DIY the openings, he said reassuringly, 'Don't worry, You'll be fine' ..... then he qualified that by saying 'Well at least if it all falls down, you only have yourself to blame' - I think the last comment was tongue in cheek but it's quite a prospect to start chopping away at brick and making holes if you have never taken on a job like that before. (I've noted your comment about taking it easy with the brickwork)

 

[Richard C]

Did it take long to complete your job?

It took around a day to complete each window (opening) with lintel installed & make good but most of the time was taken up by the softly, softly approach of drilling out the mortar & internal blockwork so you don’t have to bash things too much! Fitting the window & sealing is about an hours work next day when the cement has gone off.

Interesting they cut the hole on the same day. I was going to prop mine, cut and bed the lintel in. Leave it a few days to set and then cut the hole for the window.

I've got six openings to make, so by the time the mortar for the lintels has dried out I'll be ready to start slicing holes in the wall with the wall saw I'm hiring from HSS.

I spoke to my building surveyor and told him my plan to DIY the openings, he said reassuringly, 'Don't worry, You'll be fine' ..... then he qualified that by saying 'Well at least if it all falls down, you only have yourself to blame' - I think the last comment was tongue in cheek but it's quite a prospect to start chopping away at brick and making holes if you have never taken on a job like that before. (I've noted your comment about taking it easy with the brickwork)

Once you’ve taken out the top layer of bricks to get the lintel in (& considerably more of the internal blockwork), you may as well open it all out to size as the rest wont be providing any real support - I’m a qualified engineer so at least I understood that bit! You only need to leave the mortar 24 hours before fitting the cavity closers & windows.

As for using a wall saw, forget it you will be there forever! Go hire a giant, mother fu**er, petrol driven beastie with a 12 inch diamond cutter! If you’ve never used one before, it will frighten the bloody life out of you (much more than a chain saw!) but it will cut an opening in minutes! Use this for the outside brickwork & then drill through the internal blocks from the outside & chisel through, it saves all the dust.