House / Building structural question ?
- Thread starter hammerswinger
- Start date
Sponsored Links
This engineer is like many other professionals; once they make a decision, they stick with it even when shown it's wrong,
It strikes me he hasn't actually told you how to fix the bolts to the padstone, or to drop the beam over the padstone, There won't be very much space in the padstone between the bolt and the surface of the concrete.
It doesn't stop the beam rotating (by this, he either means the small upward movement of the beam over the padstone as the beam deflects, OR, the slight tendency of the beam to buckle sideways). Neither of these effects will be in the least reduced by two little bits of concrete fixed to the ends of the beams.
Your problem is that, being in the calcs, your building inspector will require those bolts; (fwiw, HE probably won't know how to fix them either).
The guy who did your calcs is not an engineer, he's a nit.
It strikes me he hasn't actually told you how to fix the bolts to the padstone, or to drop the beam over the padstone, There won't be very much space in the padstone between the bolt and the surface of the concrete.
It doesn't stop the beam rotating (by this, he either means the small upward movement of the beam over the padstone as the beam deflects, OR, the slight tendency of the beam to buckle sideways). Neither of these effects will be in the least reduced by two little bits of concrete fixed to the ends of the beams.
Your problem is that, being in the calcs, your building inspector will require those bolts; (fwiw, HE probably won't know how to fix them either).
The guy who did your calcs is not an engineer, he's a nit.
Some years ago there was a hospital case where a surgeon had to amputate a man's diseased leg. He amputated the wrong one, but he knew best - he was the expert.
Aye the experts don't always know best do they 
I did think that once the calcs were submitted the building inspector will want to see the steels fitted as specified which everyone seems to think is well over the top.
Is it actualy possible to use a 440mm long padstone if the return is only 3 bricks on the outside?
Cheers.
I did think that once the calcs were submitted the building inspector will want to see the steels fitted as specified which everyone seems to think is well over the top.
Is it actualy possible to use a 440mm long padstone if the return is only 3 bricks on the outside?
Cheers.
Sponsored Links
440 seems quite long; assuming your inner skin was lightweight block,
a padstone that size would suggest a load of around 55kN, which seems high for a modern house.
a padstone that size would suggest a load of around 55kN, which seems high for a modern house.
The inner leaf is standard concrete block the sort used in 1970, the SE has assumed 3.5 n/mm2 for it.
The end reaction of the inner steel is calculated as being 49 kn...the outer steel being 36.2kn.
Cheers.
The end reaction of the inner steel is calculated as being 49 kn...the outer steel being 36.2kn.
Cheers.
Looking at the pic of your house again, I would say that on reflection the load on the inner skin will be about right. The inner skin is usually the heavier-loaded as it normally carries the floor load and - in your case- probably one-half the load from the roof trusses as well.
In that case, a 440 long pad is about right for 3.5N block.
(Fwiw, in that instance I would have used a single 203x203x47UC with 250x6 steel plate tack-welded on top to pick up the cavity wall. Padstone would bridge both skins; and NO bolts!)
In that case, a 440 long pad is about right for 3.5N block.
(Fwiw, in that instance I would have used a single 203x203x47UC with 250x6 steel plate tack-welded on top to pick up the cavity wall. Padstone would bridge both skins; and NO bolts!)
We have a Trussed Purlin in the loft so only 1/2 of the rear roof elevation is on the inner skin, the calcs have a diagram of this so I assume this has been taken into account.
Cheers.
My SE has specified 254 x 146 x 43 UB for inner & outer leaf. Rather than having a 254mm downstand I want the floor joists (approx 8 1/4 ") to run into the steel which will minimise it.
Using the steel you have mentioned it appears there would be no downstand.
May be a change of plan could be on the cards....
Cheers.
Thanks for the diagram tony, Sent you a pm.
Just wondering if it's worth changing my plans, or my SE
Cheers.
Just wondering if it's worth changing my plans, or my SE
Cheers.
Hi,
Just had a look at the dimensions of a 203 x203 UC and notice that the depth Between Fillets = 160.8 mm.
Our floor joists are approx 206 mm (seems a strange size) so this would require notching of approx 45mm which seems quite a bit.
I'm guessing that fitting timber into the the fillet and using joist hangers would be ok & a better option?
Cheers.
Just had a look at the dimensions of a 203 x203 UC and notice that the depth Between Fillets = 160.8 mm.
Our floor joists are approx 206 mm (seems a strange size) so this would require notching of approx 45mm which seems quite a bit.
I'm guessing that fitting timber into the the fillet and using joist hangers would be ok & a better option?
Cheers.
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
