I am considering raising my kitchen/outhouse roof as it is too low.

The ceiling height is just over 2 metres, it is original but i think it used to be a toilet and something else, coal shed perhaps as that is what my neighbours looks like, my neighbours is divided in two lengthways, where mine is one room and part of the kitchen.

The house was built in 1938 has a cavity which is probably only just about an inch wide!

It currently has a lintel which looks too narrow but i guess it is fine? as it looks old and there have been no issues!

I would like to raise this up, im looking at replacing with a 195mm wide I Beam ITG lintel? due to the cavity width, which seems to limit my choice to solid wall lintels or should i do two separate lintels for each leaf, this is on an external normal two floors semi detached house so is a load bearing wall

I want to sort all the facts out before i go to building control as i may leave it where it is as there are to many potential issues, but just raise the roof anyway by approx three brick courses

Any help would be appreciated

I can't quite get my head round what you want,but if you are raising the height above the lintel then you could insert another above it ,bigger and stronger without the need to remove the existing.

Or when it's done you could remove the lintel and old window and fit a bigger newer window up to the new lintel.

Pics would help.

A nice wooden lintel should do it, just ask Mr O'Reilly

Hi Thanks for replying!

I wish to increase the head height of the whole room (lean to part) so i want to raise the lintel up by 3 courses at the opening of what would be the back of the 2 story house, then raise the lean to part all 3 walls by 3 courses and fit a new roof at the new raised height

There is also a massive metal tank in the roof space which cannot be removed without either cutting the tank into about 10 bits or removing the ceiling joists or the roof, this has prevented me from getting proper insulation in there so this work would achieve everything i want just a bit unsure on the technical points

My house ceilings are 2.6m high but the end of the kitchen which is the (single story lean to extension) is just over 2m

I want to raise that to around 2.3m and drop the rest of the kitchen to 2.3m so it does not feel to claustrophobic at the end also so i can fit a pelmet to the new kitchen units when fitted as currently there is no room above the units if i fit at the correct height
i will upload some pictures later today

Any help is appreciated

Definitely wont be wooden so no need to worry about that! amazingly considering the age of the house it already has a nice sturdy RSJ but which looks a bit narrow though for two leafs and a cavity?

Yes photos will help. Your lean to part. Is it single story with a mono pitched roof?

If it is then when raising the wall I imagine it will effect the roofs degree of fall.

Here are some photos there is plenty of space to move the roof up 3 courses


Lintel resting on inner leaf on side wall



Lintel resting on half a brick gas pipe is no longer in use so will be cut out also want to remove the return so the wall is straight this is towards the middle of the back of the house so no issue with space

This is looking up from directly below the current RSJ


This is the lean to from outside


This is the metal tank that is preventing any proper insulation


Metal tank again


And this is the drop and RSJ from the first part of the kitchen that has 2.6m ceiling height

Any help especially with corbeling into the cavity to achieve the 150mm bearing for the RSJ and any issues I could have with building control

Cheers

You will need building control involved.

I would invite them for a pre commencement visit. You may have to pay for that ,but most inspectors appreciate that you are being diligent.

That wall will need supporting higher up during the work. So that the three courses of bricks can be removed safely. Remember it's not just the three courses,it's also the height of the new lintel if you want those two ceilings at the same height as one.

I can't advise on the new lintel size and strength. You will need an expert for that. But you should be able to buy one of the shelf at a builders merchants.

To carry out the work I would remove the lean to roof and ceiling completely. you also may want to think about that small gable as making good will show poorly. A new gable will look much better.

You will also have access to the top of your brick cavity. Have a good look down to check brick ties etc. a good time to have it insulated.

The new lintel will need concrete bearing pads installed. Either cast in situ or cast in a mound then laid on mortar.

It needs to be done very correctly as you will need the sign off certificate from building control to be kept with your other house documents.

Ask away any other questions.

Eta. What's that plaster area on the right above the lintol? Old window/door?
That existing steel is waaaayyy to inadequate.

Thanks, yes i intend to take the complete roof off when commencing the work, which will make the metal tank easier to get out too, i also wish to do this properly
Im just concerned that I am not going to be permitted to do the work and then building control insist on a new lintel with proper 150mm bearing surfaces being put in where it is now so money and time spent to achieve nothing different, if that makes sense!

My biggest concern is the Load bearing surface on the side wall as the bricks are not wide enough to get 150mm bearing unless its permissible to go into the cavity with a corbel, worst case build it out into the room im more unsure of the regs and rules and what is permissible and what is not also it is not far from a door, but that will be bricked/blocked up then there is the thermal insulation side of things as the RSJ would be up to the cavity that is uninsulated

Not sure what you mean by the gable? i was planning to remove all the cut bricks and build it up 3 courses as per the rest of the roof is this what you meant or did you mean knock it down and start again, when looking at it from inside where there is no render it appears very well built and solid etc.

Many thanks Rich

Do you mean the last Photo?
If so that's the original plaster that was part of the kitchen its just not come loose yet, this was all covered with plaster board so was not visible until Saturday
The door under the lintel is the original pantry that also housed our gas meter now moved this is also pictured with the lintel resting on half a brick with a gas pipe under the lintel and an old lead water pipe running up the wall. This is the back of the house so plenty of space to extend the RSJ along also hoping to remove that return, on the external picture its is the left side of the lean to as per picture

Look at the picture of the steel. On the left I can not see any bearing problems.

As you say that wall is going up 3 courses . So as I see it that door lintol will have to be upgraded to a full with lintol and the new steel will then bear at a higher point so it's not normally a problem inserting another lintol above/on top at right angles.

The right hand side. Do you want to remove that nib? If so you should still be able to insert a concrete pad at full width then insert the steel on top.

There might be a bit of plaster damage in the next room corner but nothing that can't be made good.

Thanks again!
Making good is not an issue so thats fine, the door on the left side of the last photo will be blocked up so would i still need a lintel there my thoughts are that i wont, unless because of lack of brick bonding into the old brickwork other than a few ties it would be required to improve the wall stability?

what are your thoughts regarding the left bearing point what is the best way of creating a decent bearing surface and not breaching and regs regarding the cavity cold bridging etc. if i could go right across touching the outer cavity i dont see a problem but is it permissible to do that?

If the door is to be bricked up then no lintol needed. Make sure the new brick/block work is well bonded to the existing.

Normally on cavity work you would have two bearing pads not bridging the cavity.

I imagine the new lintol could be a pair of rsj steels bolted together once inserted. That should make the installation a bit easier.
But as I said before that will depend on the professional you employ to work out the loading stresses.
Or the building inspector may just say put in a pair of 8x4 rsj,s bolted together.

Academic I suppose, but that RSJ might already be later work from the original building date?, Ive not seen that sort of lintel bridging arrangement on cavities before - you learn something every day!.

My house was built 1909 and the span across the rear cavity consists of 2 off original 4" x 7" wooden beams, bolted together with spacer blocks to maintain the cavity space. However a hundred years of water ingress and worm now means I have a bow in the central area probably dropping 2" now. Scheduled for replacement later this year or next.
It may be that building control still permit wooden beams to be used, maybe C24 grade or higher.
But I think steels are going to be the way to go for your job, with the necessary fire protection standards on the plasterboard cladding over the steels as it would be defined as 'new works'.

Are you doing all the work yourself?. having kit to hand such as some acrows and some Strongboys will make for an easier life.

I had an outhouse similar to yours rebuilt last week, the 5.4m flank wall completely removed and the original slate roof supported on four strongboys (spacing calculation stipulations were fine for this particular loading) whilst all that was going on for a few days. They're simple devices but very effective.

Hi i will do most of the work myself dont have the strongboys but hired them last time i did this sort of thing used to have acrows to hand at work but need to check otherwise they will be hired too.

Building controls came around today and he confirmed that i can use 152 x 89 universal beam one for each Leaf bolted together with a spacer

Everything else is fine too and the bit that i was really unsure about was the load bearing for the RSJ which has been confirmed as 100mm and its fine to rest on just one leaf so thats a relief as i was concerned that what i wanted to do was not possible

Thanks to all for all the advise and info

Glad it turned out uncomplicated for you.

If you lived closer, you could have borrowed mine!.

Awfully Kind of you JonH

Sadly nowhere near the South of the west but was on holiday down there 31st may to june 1st and we had some wonderful weather whilst everywhere else was raining!

I could really do with another Holiday! never mind must just get on with it!

I can add nothing to this thread but it's been a really interesting read

Hi guys another question!

what is the best way to replace the RSJ?

I Will support both internal and external walls with strong boys 2.1 m span so minimum 3 but may put one at each far end of the wall and evenly space another 2 between or is that ott?

What's the next step? Remove old RSJ build up wall then place new uni beams in place?
Or do I need to remove RSJ then position new beams, acro them up then build underneath upto the beams?

Just wondering if there is any issue leaving on strong boys with no rsj's in place whilst building up the wall?
Also how long to leave mortar before loading with the beams

Many thanks R

Many ways to achieve the end result, I think.

Maybe I would Strongboy the inner & outer leafs (four would be good but 3 would probably suffice if the wall does not support the upstairs flooring joists) to remove the existing steel, then build/make firm the pad surfaces for the new UB's. Space between the pad surface and the walls above to be just enough to cater for the UB's, a bit of mortar, and slate packers.

Leave the pads overnight and slide up the new steels the next day with a mortar bed placed on top to marry up to the brickwork above, then packing out the space on the concrete/brick pads up to the UB with slate only - hammering as much in that will go in to physically force the UB's hard onto the wall(s) above (old roofing slates of various thickness for you to select from is ideal - but make sure its real stuff and not the composite modern slates).

Well... thats one idea anyway !.


Strongboys - the main issue with any form of temporary support is your foundations. If you are unsure about the strength of the floor that the Acrows are going to stand on, for the strongboys, then you should really consider placing bearers across the floor first to spread the loading downward. Sleepers, or half sleepers, are good for this.

well fingers crossed roofs off so the old beam is coming out Saturday and the new ones are hopefully going in on Sunday

Have now discovered that the original extension building is single skin and there is no cavity and it's all a bit of a mess so I may be spending a bit more time than I hoped with the rest of the building
Most of the roof timber is rotten at the wall plate and they used a floorboard for the ridge board
So a bit more money needs to be spent and a bit more time but we will get there!
Cheers for the reply!

Mmm I did suspect that out building was single skin.

So you could metal stud and insulate the inside when finishing.

Hi, right old rsj is now out no mishaps so far (touch wood, touch wood!!)
I have laid my engineering bricks level etc. i was going to build up with engineering bricks but went against that due to the metric and imperial difference, which leads me to my next questions

As im using metric engineering bricks the finish height of the bricks leaves a much larger gap than i anticipated

I was told by the building control officer to use the i52x89 so whats the next step do i place packing under the bricks to move it up or do i have no alternative other than buying a padstone? or can the bricks be placed on there side?
Or I have some old proper victorian slate (fire mantlepiece) so this is the decent stuff me thinks will that be ok? fine by me but i dont want to dissapoint the building control officer

Cheers

I know a lot of folks use slate,but to be honest it's a diy.

Get the steels onto a concrete pad stone then pack with metal spacer's if need be.

Probably a bit uneasy about thick pieces of slate - solid mass (padstone etc) should really be a good adhesion to the support below it and be as close a gap for the UB to fit as reasonably possible, and then use slate as slivers for hard packing.

If you were doing a newbuild then its easy to place the UB's on padstones direct and continue building up.

But retrofit work it is necessary to be using uncompressable packers of some material or another that also provides a good grippy-ness with the mortar you drive in the gap also.

Ok I spoke to the building inspector and he was ok with some slate in between a course so the mortar joints were small, but the final brickwork height is reasonably near, then it will be metal plate/shims under to raise height

I'm about a day behind now and just seem to be uncovering bodge after bodge?

The inner leaf on the outside of the house is normal brick but without a cavity so the extension inner wall is almost an inch out of alignment ( dog legged) not obvious as the back door bridged this gap
The opposite side the inner leaf is built with bricks on their side no cavity, this was misleading as they have dot and dabbed on top of the original plastered/rendered wall so it wasn't obvious until taking the plasterboard off

The BC Officer is aware of all this and is not fussed

So now the pads are done and rear door blocked up double skinned with concrete blocks ( they are heavy after a while) new treated timber ordered for the roof
Tomorrow I'm bricking up one side to the new level and chopping out the other side for the new door and then bonding with concrete lintels before bricking up or that's the plan!
Having to chop a concrete block for every course on the back door was slower going than anticipated
Well it's "keep calm and carry on"!
Cheers for the replies

9 inch disc cutter with a diamond blade is your friend .

With a water feed as well - .... zero dust through the dwelling !

Is it all finished now?