Structural Engineer Drawings

[165EatonPlace]

We are planning on having our house (bungalow) internally remodelled and this will involve removing 8 internal walls. The structural Engineer has completed his drawings (he didn't visit the house but used the Architect's plans). He has specified 8 RSJs be inserted. Some walls run parallel to the gable end, whilst others run perpendicular. Surely not all the walls are load bearing. Why would every wall require an RSJ when removed.
Any advice much appreciated. Thankyou

To stop the roof from falling in.

Seriously. You can't just take bricks out and expect what's left to be self-supporting - that's not how houses work.

Probably to tie the walls together otherwise the roof may cause them to splay out.

Thankyou Sardine. Yes I know what they are for. But I am surprised every single wall is load bearing. They are all internal walls

If you are taking 8 walls out, there can't be much left internally at all!

When you put a steel in, it clearly needs support at both ends. They also have a finite distance they can span. I suspect some of your new steels are there to pick up the ends of others or to reduce long spans. Even if the wall they are replacing is not load bearing, they are needed to support other steel.

Structural Engineer here. You still need to hold up whatever is above those walls @165EatonPlace. Plus the walls act to brace the house against lateral loads such as wind. So even if they’re not holding anything above them, they’re stopping your house collapsing.
I feel your pain though. RSJs are expensive!

Thankyou NothingIsWrong
There are currently three bedrooms, one of which is very small. By removing two walls we will lose a bedroom and create a larger hallway/reception room.
By removing 2 other walls we will lose a walk in pantry but create one large kitchen dining room.
By removing 2 other walls and a floor we will lose a disused toilet and coal bunker beneath but gain a double height lobby.
We will make a new third bedroom from a "cellar" room (a room at ground floor level). It is an unusual property built on land that slopes from front to back and side to side.
Thankyou sandieshaw for your explanation.

From your description it sounds much more complicated than a standard "knock two rooms into one" scenario. Without seeing the plans I can't comment specifically, but when you are dealing with multistory properties (which it sounds like it is if you are talking about cellars and double height lobby), you need to think very carefully about the load paths through the house to ensure that all the load is carried to ground safely. Walls can be non-loadbearing, but carry lateral wind load, so it can be more complicated than a quick glance might imply.

It sounds lovely by the way!

If a structural engineer has said they're required for the plan to work then that's sort of the end of it! I took what my engineer said as gospel, as did the BR inspector and the planning dept... It's why they get the big bucks!

We have removed 5 internal walls from our house. Ok, not a bungalow but RSJs are used to support structures to ensure you don’t have pillars! DH is a structural engineer and Design is crucial so unsightly pillars don’t get in the way. We have a corner of our house supported by RSJs. It’s been opened up to incorporate the old porch. It’s great because there are no pillars. I think we have 5 RSJs on our ground floor holding up various walls above. As DH says, the weight of the roof/walls and joists must go into the ground via external walls and foundations if you are taking out load bearing walls. It’s like a jigsaw puzzle. If a wall isn’t load bearing it might not be relevant in the overall structural design but what surrounds it must be designed to be structurally sound.

In the overall scheme of things, RSJs are not that expensive. Retaining walls for properties on a slope are a lot more!

B Regs people rarely know their arse from the elbow regarding more complex structural design.

@PresentingPercy

B Regs people rarely know their arse from the elbow regarding more complex structural design.

But they still have to be kept happy as they sign it all off. No justice in the world but there you go.

Thankyou for some very informative replies.

The steel beams are not necessarily there to just support vertical loads ie from roof/ceiling over. With so many internal walls removed its possible that the SE has had to consider the overall stability of the building and that some of the steels might be providing lateral support to the remaining walls which was previously provided by the walls being removed. Are there steel posts/columns as well?

metro.co.uk/2020/11/03/two-houses-in-chelsea-collapse-during-basement-conversion-as-40-evacuated-13526342/?ito=facebook%7Csocial%7Cmetroukfacebook&fbclid=IwAR2zRLXVdCwrVt2NmFvlnaPneXa6UagVpgQT6CWhOQg-aSutE75orPAP1J0

Always better to do it properly the first time!

NothingIsWrong
Thanks for the link. Might stick with the disused toilet, coal bunker and 1 coal fire we currently have to heat the whole of the property.
Seriously, it will be the worth the stress, upheaval and money to do the project.