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Bisf - Doorway at foot of stairs into Shed  



Hi all,

I am seriously considering a single storey side extension on my house, extending off the old  shed/utility/toilet lean-to.  I have been researching these houses a long time and have had this house in the family for over 20 years so I'm not new to them.

My issue is this, what support is needed when removing the diagonal cross brace that conveniently runs exactly when I'd like the door to go?

I know many people have done this but there is no definitive answer as to the best way to achieve this.  Could anyone help?

For reference (and in case any one is interested)  this is what I'd plan to do unless others have better advice.  

1.  Remove diagonal brace.

2.  Support the two vertical steels this was connected to with a steel above the door frame, kind of like a lintel of sorts.   I figured this will help to stop the frame buckling inwards.

3.  Tie-in the two vertical steels to the lean-to.  Possibly bolting them or fashioning some other way...

Any help would be much appreciated.  If it's a safe and doable job, then I'll be going ahead with the extension for sure! 


3 Answers

I think your plan is safe and doable. And I would suggest for you to go ahead with your extension.


Thanks for the response kjones.  I wonder if anyone has any pictures or more info on the matter?

When I do get around to it, I'll certainly be adding some images as this must be something that people with these houses often think about doing...



I have seen many instances where a doorway has been installed at the bottom of the stairs to provide direct access to the outhouse or side garage in various BISF houses.

The main obstacle to installing a similar doorway yourself, is of course the diagonal steel brace that forms part of the houses steel framework, which is situated directly behind where the door would be located.

As this brace is part of the original support structure and the fact that I am not a qualified structural engineer myself, I cannot provide professional advice on the removal of any structural supports for obvious legal reasons. As is standard practice, I can only advise you to seek the advice of a professional structural surveyor before undertaking any work yourself.

With that being said, I can share with you some of the answers to previous posts on this same question but please bear in mind that this should not be viewed as advice on which you should act.

I'm also pretty sure we have discussed extending the existing outhouse too, including my own experience on one of my properties.

Let us know what you think once you have gone through some of the above links and if you have any further thoughts or concerns.


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