Opening up a wall - Best way to Prop the wall

[Art Martin]

Hi All,

I am opening up a doorway(essentially widening it by about 1.5 metres), and I am looking for a bit of advice regarding the best way of propping the wall while I open it up. There is some roof and ceiling load on the wall. My main question is how to handle the load in the time when I take the previous beam above the doorway off, to when I install the new beam.

I had a engineer friend engineer the sizes for me, but he's not a builder. I feel pretty comfortable doing this myself, but just wanted advice on other people experience as to common ways of achieving this.

Thankyou.

[silentC]

I reckon a solid bit of timber up against the ceiling either side of the opening (depending on what is above) and an acrow prop at each end. You can hire acrows.

[dazzler]

What about putting a piece of 4 x2 near the edge where you are widening and force it in to take the load. (slightly angle the top cut so it can be belted in)

Cut out the new section of wall stud etc and then cut through the top plate either side of the 4 x 2 so that you end up with the 4 x 2 with a piece of top plate above it.

Then brace each new corner and finally take away the middle bit.

[rat52]

Silence is correct but take the board against the ceiling to the next joist past the opening.

If you can't afford acro props the use 90x45 timber with wedges under to take up the slack.

This takes care of the ceiling support but if the roof is propped off the wall you would then need to support this separately

I assume the wall is timber stud.

[Metung]

I'm no expert but I agree with Dazzler. Put in your jamb studs either side of the proposed opening, two each end, one full length and one notched for the lintel. I would use a 190X45 F17 KDHW lintel. Notch out existing intermediate studs to take the lintel. Place and fix lintel to existing and new studs. Cut away existing studs below lintel to create opening, existing studs become jack studs. To be on the safe side you could temprorarily prop either side as suggested bu Silent. I suppose infact I agree with everybody.

[silentC]

Actually, I've changed my mind. Do it Metung's way. Don't forget to allow for the door head when you locate the lintel...

[MrFixIt]

Hi

BEFORE you do ANYTHING, look inside the roof space to check and double check what if anything is being supported by that portion of the wall you intend to widen.

The job methodology will vary a little depending on the wall type, brick or timber.

If the wall is NOT bearing any roof load then you will have less to worry about.

It is not wise to support the ceiling only on either side of the wall, as any movement of the wall may cause cracking at the wall/ceiling cornice joints. Correctly supporting the wall will automatically support the ceiling areas and help prevent/minimise any ceiling cracking. The mere fact of installing "ceiling" support could very well induce cracking. You will also find it VERY difficult to ascertain when you have "supported" the load as the acrow props will just keep on adding pressure against the ceiling.

The PROPER way to do this is to make at least two holes in the wall just ABOVE where the new beam is going to be installed. Your timber supports 100x50 - 90x45 (OR 150x45 if you are breaking though a load bearing wall), go THROUGH these holes and are supported either side of the wall on ACROW props. If you cant afford Acrow props then WAIT UNTIL YOU CAN it WILL make the job a whole lot easier. You will also physically see the support "in action".

You should be able to prepare for the job and be able to utilise the acrow props for only one day's hire (maybe even half a day?) - WELL worth the cost

So you make your holes, have the support timber ready to place in situ. Prepare as required to be ready to remove the old beam/plate etc. Prepare as required to install the new beam, remove plaster/gyprock, possibly remove some timber if it is a timber wall.

Obtain the acrow props, support the wall, remove old beam, insert new beam, (add timber suport where required if timber wall) or pack as required on brick wall. (if you have to pack under the beam on a brick wall, don't use timber packing as it may shrink, use fibro cement packing)

Remove support - return acrow props - and continue wall repairs/patching - fill in holes where support beams passed through.

BTW if it is a load bearing wall and you don't have any timber for the through wall supports, hire a couple of 3m scafolding planks and use them on edge (of course) for your support timber - the planks should be at least 200x35 plenty strong enough on edge.

Simple really just requires a methodical approach.

HTH

[julianx]

Hi
I would generally use a method as described by metung, although you should get your friend to check the size of the lintel ( the size will depend on a lot of things ie roof span, tile or sheet, which story of house). Just make sure he engineers it to be about 2 thirds the width of the stud so you can check it into the existing studs.

[Art Martin]

Thankyou all for your comments so far. Certainly some good ideas. And just to clarify, I've had an engineer work out all the specs, but he wasnt sure from a building perpective the best way.

MrFixIt...this is what I was considering doing, however, can I clarify with you that I am reading your post correctly.

Are you saying that I should lay a horizontal timber support running perpendicular through the wall above the current doorway beam, and just below the top plate, whereby the horizontal timber support would be supported on either side by acrow props. I'm visualising a sort of perpendicular stud lintel arrangement, where the acrow props are studs, the timber support is the lintel, and this sits in a perpendicular direction to the direction of the wall. Is that what you meant? If so, would you necessarily need acrow props or could you use timber for the vertical support.

Again, thanks all for the comments so far.

[MrFixIt]

MrFixIt...this is what I was considering doing, however, can I clarify with you that I am reading your post correctly.

Are you saying that I should lay a horizontal timber support running perpendicular through the wall above the current doorway beam, and just below the top plate, whereby the horizontal timber support would be supported on either side by acrow props. I'm visualising a sort of perpendicular stud lintel arrangement, where the acrow props are studs, the timber support is the lintel, and this sits in a perpendicular direction to the direction of the wall. Is that what you meant?

Yes, if I understand YOUR interpretation correctly

See the image below...

Position the support beams to provide reasonable clearance for the new beam while Keeping as much of the wall as possible above the support beams.

If so, would you necessarily need acrow props or could you use timber for the vertical support.

Yes, you can use timber for the supports, but you do then have to cut them reasonably close to size, then you have to have packing and or wedges or as in most cases you have the support post on a slight angle (5&#186 so that you can "hammer in" the base of the post to hold it up and press against the beam it is supporting. To do this inside the house, you will no doubt have to place a large peiece of timber/ply beneath the support post so as not to damage the floor covering as you move the post. (Though of course you will still need some form of floor covering procection under the props).

I just did a job replacing some beams on a pergola. I supported the existing rafters on another beam held up on acrow props. I would previously done this with posts as you are proposing, but the acrow props made it SOOOOO much easier. (BTW I was able to borrow the props from a friend so that made it cheaper for me )

Hi
Just make sure he engineers it to be about 2 thirds the width of the stud so you can check it into the existing studs.

This is INSUFFICIENT for safety AND SUPPORT purposes! The new beam should extend into the existing wall to be FULLY supported by at least ONE FULL stud, or a MINIMMUM of 200mm if it is a brick wall. You could check it into an existing stud IF you add a NEW stud at each end providing support - but then the need to check in is minimised.

If this is a load bearing wall, depending on the size and cost of the beam it would be better to have the new beam extend over two studs as this not only provides addtional support, the load on the beam helps keep the ends of the beam pressing down on the supporting studs.

HTH

[Art Martin]

Thanks MrFixit. The picture and explanation you provided was exactly the way I was visualising doing the job. I'll definately be doing it that way.

Thankyou everyone else for your comments and input.

[Metung]

Peter, I think I am missing something obvious in your proposal but I can't fathom out exactly what your two pieces of timber through the wall are actually holding up. I imagine there should be something between the top plate and the pieces of timber to transfer the load or am I talking the proverbial again

[ozwinner]

And dont forget to put a plank under the acro props or the load may push the props through the floor if its timber.

Al

[rat52]

Art,
Fixit is correct but you only need to needle a brick wall.

I have done this type of job for both brick and timber wall including putting strutting beams in roofs so an entire wall can be removed and it can be done as I and others described.

As I asked before where is the point load from the roof to the wall. Is it over the opening or to one side . Is the wall brick or timber .Internal or external wall.Are the ceiling joists at 90 deg to the wall or parallel. Is the roof tiles or iron,truss or conventional.

All these things factor in doing a safe job and are needed for good advise.

[julianx]

This is INSUFFICIENT for safety AND SUPPORT purposes! The new beam should extend into the existing wall to be FULLY supported by at least ONE FULL stud, or a MINIMMUM of 200mm if it is a brick wall. You could check it into an existing stud IF you add a NEW stud at each end providing support - but then the need to check in is minimised.

I think you have misinterperated what I was saying,I wasn't suggesting you only check the ends of the lintel two thirds of the way into the jamb studs, these will need at least one full stud. I was suggesting a process for installing the lintel. which is - select a lintel that is narrower than the depth of the existing studs then check this into all the existing studs above the opening. This can be just under the top plate or just above the opening. Then fit the right number of jamb studs under the ends of the lintel. The bottom of the studs in the new opening can then be cut off leaving the top of the studs as jack studs. If the lintel is directly under the existing top plate then the opening can be framed up with a lintel trimmer as a head.
Hope this is a bit clearer