Regs regarding bearing of outside wall lintel

[cyclonebri1]

Hi, Hope some knowledgeable person can help.

We are doing a wrap around ground floor extention, ie, on one corner of the house.

All has passed planning and building regs and know the chosen builder is on scene.

We need info into the knocking through of this corner into the new extension.

To try and make it clear, the existing corner stays, but we wish to remove as much as possible of the back wall which will extend the old kitchen into the new one.

The wall is standard brick/cavity/block of 275mm.

How much wall do we have to leave in on the back side corner to comply?

I hope that's clear, it's difficult for me to explain, and I couldn't even try to figure how to put a drawing up here,
Cheers,
Bri

 

[freddiemercurystwin]

So you've had a full plans Building Regs Application approved, how did it get approved without input from a structural engineer?

Or are you getting Planning confused with Building Regulations?

 

[Static]

Size of pier will depend on load from openings as well as size of existing foundations.. i would also ask the above question.. what was put on the building regs plans.. ?

 

[DevilDamo]

Have you/your architect indicated these openings on the building regulation drawings? If so, they should have specified beams/padstones to support the load above and if they didn't have a SE onboard at the time, they may have either sized up steels subject to SE approval or would have noted the beams are to be confirmed by an SE, who would have then provided you with the information you require.

The BCO could also advise you on these details, but any new beams would be subject to SE's details and calculations.

 

[cyclonebri1]

So you've had a full plans Building Regs Application approved, how did it get approved without input from a structural engineer?

Or are you getting Planning confused with Building Regulations?

No confusion, to make clear;

The plans were drawn up by a structural engineer, we have used him before and when detailed calcs were needed for something quite similar he provided them.

This has been fully trough both building regs and planning consent. No confusion.

We are using a private BI, again we have used him before.

The SE speced the size of beams RSJ set on concrete padstones and bolted together. What he dindnt spec other than buy us taking a measurement from the scaled drawing is the length of wall that must be left in at the corner.

Whats actually happened is I think that the builder thinks he can get away with just taking out the existing window and door, they butt up to each other and will share a common lintel. As a result he didn't price for knocking out to the correct width and replacing with the correct spec lintel.

Just trying to get a rule of thumb regrading the min amount of corner that has to be left, before we take it up with the builder and the SEngineer. Fore armed and all that.

 

[freddiemercurystwin]

Just trying to get a rule of thumb regrading the min amount of corner that has to be left, before we take it up with the builder and the SEngineer. Fore armed and all that.

I'm not sure there is one really, in anycase it will be the SE who decides as it will be his head in the noose, so to speak.

 

[Static]

As said above its down to the SE.. without knowning every single little detail about the job it would be almost impossible to give a "rule of thumb"..

Size of pier should have been included in the calcs with a design check..

 

[cyclonebri1]

Now sorted by talking to the SE. The sizes of beams are greater than that supporting the existing walls so the buider has no option but to replace.

The confusion was the interpretation of the buider of the drawingwhen he quoted, I must admit I can find no reference to removing additional brickwork and there is no dimension on the plans, but it is clearly not as existing.
The measurement incidentally was 350 measured internally in this case.

Now to renegotiate with the builder

 

[freddiemercurystwin]

Might be an idea to ask what else the Bozo's apparently 'forgotten' or 'misinterpreted'!