More builders advice please?

[-Ralph-]

This is the rear of my new house (not the exact house, but exactly the same house style from the same builder)

http://i227.photobucket.com/albums/dd82/colinbal4/Hawthorne/TheJittyRear.jpg

This is the current floor plan for the ground floor

http://i227.photobucket.com/albums/dd82/colinbal4/Hawthorne/FloorPlanGroundE.png


See the little extension at the back that makes up half the kitchen?
Would it be possible to extend the same roof all the way along the back of the house, to achieve this?


http://i227.photobucket.com/albums/dd82/colinbal4/Hawthorne/FloorPlanGroundExtended2.png

There must be an RSJ over the kitchen at the moment? Would I be able to put another one in over the rest of the kitchen, welded to the existing RSJ and supported on the kitchen/living room wall, and the outside living room wall? Or would I need to take the existing RSJ out and put a new one in the full width of the house from outside wall to outside wall?

Would this leave a beam in the ceiling or any protruding pillars required on the interior walls?

About how much do you reckon it would cost?

Thanks

[Ed]

Ask the builder for the structural engineer's calculations. You will need your own engineer to calculate the loadings on a new beam. A builder might be able to do it but they generally don't carry professional indemnity insurance, and besides the building inspector will ask to see the calcs.

Nice gaff!!!!

[MisterTommyH]

The beam thats in there already will be sitting on the corner between the utility and the kitchen.

The second plan doesn't have this wall anymore so you'll have to put a completely new beam in. The span is greater so the beam will need to be bigger (in capacity - it might be possible to get one of the same depth to work though). You'll also need another beam (possibly re-use the existing from over the kitchen) to sit over the lounge/diner to support the external wall and first floor above.

From eyeing it in this looks like it might sit just be over the double door you've got shown so you'll need a decent beam over that door rather than a simple lintel (unless you want to move the door so that it's not central in the panel).

Also both beams would be bearing onto a single leaf wall between the diner and the kitchen - you'll probably need a pier there to get a decent bearing for both (This assumes that the existing GF wall is masonry not stud).

Finally, by doing that you'll be changing the way the load goes into the foundations - do you know what the foundations are? In most cases this shouldn't be a problem, but if it's piled or if they're very skinny then it's something worth getting looked at.

[MisterTommyH]

Ask the builder for the structural engineer's calculations. You will need your own engineer to calculate the loadings on a new beam. A builder might be able to do it but they generally don't carry professional indemnity insurance, and besides the building inspector will ask to see the calcs.

Nice gaff!!!!

Very unlikely to get the original calcs Ed. We don't provide copies on principle. For something like this you'd probably want someone to do it as a foreigner - A lot of companies would find it too small and charge the earth.

If you need calcs shout and I'll see what I can do for beer tokens. Don't carry PI though.

[Specialone]

Tommys correct, you will need a new beam spanning the new area.

If the divide wall between the lounge and larger ktichen was reconstructed and widened, you could have both beams supported from this to the outer walls.

Ive done similar to this, the architect for that job specified a 10x6 beam which was ridiculously over size (and he told them they could have a flush ceiling but only had 6inch floor joists), i got new calcs done and used a 8x8 RSJ, which also supported a 6x4 perpendicular to it.

I dont think you'll need one as big tbh looking at it.

Id be amazed if foundations would be a problem but does depend on the ground in that area, ive been lucky in the areas i work in, its good clay.

For the cost id try and go another metre out, it wont cost that much more tbh.

Between me and you, i cost extensions at approx £800-£1000 per sq metre for the shells, beams, roof windows, french doors all add to this.

A different brick can add £500 to a extension so i have to be careful with quotes.

[skeetly]

That's way outside what Reg's will allow normally.
Modern houses like that are built within certain parameters that you can read about here:

http://www.planningportal.gov.uk/uploads/br/BR_PDF_AD_A_2010.PDF

From about page 25 onwards should be helpful.

You can get round them by hiring a good engineer and using lots of money.

I did type out a big long reply with lot's of technical stuff but it was getting ridiculous and I had ended it with this picture:

http://www.darksouls-thebook.com/images/how-long-is-a-piece-of-string.jpg

:D


Good luck.

[Specialone]

Very unlikely to get the original calcs Ed. We don't provide copies on principle. For something like this you'd probably want someone to do it as a foreigner - A lot of companies would find it too small and charge the earth.

If you need calcs shout and I'll see what I can do for beer tokens. Don't carry PI though.

My structual engineer charges me £80 per calc, he gives me a copy which i copy myself then give to the BCO, they then pass it on to their 'checking' dept who just enter info in their bit of software and say yep thats ok.

Problems start when architects think they are engineers.

[MisterTommyH]

That's way outside what Reg's will allow normally.
Modern houses like that are built within certain parameters that you can read about here:


Nae sayer! ;)

It is above permitted extension (3.5m sq). So you'll need a planning approval, but unless it's tight against a side boundary I wouldn't think you'd have any problem getting it passed.

My structual engineer charges me £80 per calc, he gives me a copy which i copy myself then give to the BCO, they then pass it on to their 'checking' dept who just enter info in their bit of software and say yep thats ok.

Problems start when architects think they are engineers.

I'll do you £50 and a .pdf copy ha ha.

On jobs this size that is what I'd do, but on a big estate with multiple copies of houses and probably 300 plots we would deal with BCO direct and the developer would never see the calcs.

[-Ralph-]

Thanks v much for the reply Tommy!

The beam thats in there already will be sitting on the corner between the utility and the kitchen.

The second plan doesn't have this wall anymore so you'll have to put a completely new beam in. The span is greater so the beam will need to be bigger (in capacity - it might be possible to get one of the same depth to work though). You'll also need another beam (possibly re-use the existing from over the kitchen) to sit over the lounge/diner to support the external wall and first floor above.

OK, understood. I never thought about taking the existing beam out and putting a new beam for the kitchen, and another for the lounge (but that's why I'm not a builder :p ).

I take it having to remove the existing kitchen beam adds a lot of cost? This is basically just to allow us dining space in the kitchen or lounge (or both), so we can use the 'dining room' for something else. We only use a dining room when we have guests, and unless there's 6 or more people we end up eating at the kitchen table, so it's a waste of a room. We do need occasionally to seat 6 or more people though, but we'd be happy to do that in the lounge or kitchen.

The other option of course to keep the existing wall (and reduce cost?) is this, and there's a lot to be said for a utility room when you have a dog with muddy paws.

http://i227.photobucket.com/albums/dd82/colinbal4/Hawthorne/FloorPlanGroundExtended1.png

Still it's a 5 bed house, so there's plenty other rooms that could be a playroom, so I wouldn't spend the earth to achieve it. If it were 20 grand or less I might do it, if it were 30 grand or more I definitely wouldn't

From eyeing it in this looks like it might sit just be over the double door you've got shown so you'll need a decent beam over that door rather than a simple lintel (unless you want to move the door so that it's not central in the panel).

Also both beams would be bearing onto a single leaf wall between the diner and the kitchen - you'll probably need a pier there to get a decent bearing for both (This assumes that the existing GF wall is masonry not stud).

Would be happy to shift the door, no idea what the existing wall is. Haven't moved in yet so I can't bang on it to check! If it was a stud wall that would need a proper foundation dug and replaced with a masonry wall wouldn't it? I think that would create enough mess to knock the idea on the head.

If you need calcs shout and I'll see what I can do for beer tokens. Don't carry PI though.

Cheers Tommy, it's a Taylor Wimpey house.

[MisterTommyH]

Is it a new estate or a few years old? Do you know what the estate is called (as in what Taylor Wimpey called it when it was sold rather than it's local name)?

Theres a chance that we would have done the fnds design.

[-Ralph-]

For the cost id try and go another metre out, it wont cost that much more tbh.

Between me and you, i cost extensions at approx £800-£1000 per sq metre for the shells, beams, roof windows, french doors all add to this.

Thanks Phil.

Another metre out along the full length, or just on the new bit? If the full length I'd more or less be knocking the existing extension down and starting again? If just the new bit, how would the slope of the roof work, alongside the existing extension roof?

[skeetly]

Nae sayer! ;)

It is above permitted extension (3.5m sq). So you'll need a planning approval, but unless it's tight against a side boundary I wouldn't think you'd have any problem getting it passed.


I was on about the Building reg's :)
It's a big hole in the back wall of the house and I assumed (possibly incorrectly) that he didn't want any piers.

I can't see there being much hassle with actual PP.

[-Ralph-]

I was on about the Building reg's :)
It's a big hole in the back wall of the house and I assumed (possibly incorrectly) that he didn't want any piers.

I can't see there being much hassle with actual PP.

Thanks Skeetly

Would be nice of course to not to have piers but not too worried about piers if they need to be there (so long as they are embedded in a wall not freestanding, and would prefer to put one on the kitchen side of the wall than the living room side).

Would prefer not to have a beam in the ceiling, it's would be 6 ft from the back of what would be a 25' living room, and it would look wierd.

[-Ralph-]

Is it a new estate or a few years old? Do you know what the estate is called (as in what Taylor Wimpey called it when it was sold rather than it's local name)?

Theres a chance that we would have done the fnds design.

Don't really want to post exactly where I live on open forum (where my bikes are garaged, etc). I'll PM you.

Don't go to any effort looking for stuff at the moment though. This is just dreaming about possibilities for now. My son is getting to the age where she might be quite happy to send him to an upstairs playroom ;)

[Specialone]

Thanks Phil.

Another metre out along the full length, or just on the new bit? If the full length I'd more or less be knocking the existing extension down and starting again? If just the new bit, how would the slope of the roof work, alongside the existing extension roof?

I did mean knock that one down / extend it tbh.

I was on about the Building reg's :)
It's a big hole in the back wall of the house and I assumed (possibly incorrectly) that he didn't want any piers.

I can't see there being much hassle with actual PP.

Ive put some big beams in existing brick walls, much larger than Colins plan looks, the only thing the engineer has specified is large pad stones.

If your building new walls, i personally build that area in 7n blocks and its always passed bco approval.
That said, My local BCO's are brilliant tbh, they arent strict and by the book jobsworths, they can be really helpful and offer some good ideas at times.

[Specialone]

I personally cannot see why you would need piers, admittedly its probably a 150mm bearing for that span but with the right padstone and the right BCO it would be fine ;)

Flush ceilings are another ball game and a PITA at times.

[-Ralph-]

I did mean knock that one down / extend it tbh.

OK, didn't realise you'd get another metre out and still have an acceptable slope on the roof TBH, so that's good to know. If I went another metre out, it may give the space to put a utility room back in somewhere.

[MisterTommyH]

I personally cannot see why you would need piers, admittedly its probably a 150mm bearing for that span but with the right padstone and the right BCO it would be fine ;)

Flush ceilings are another ball game and a PITA at times.

I only think you'd need a pier if you were trying to support two beams off an internal wall (in order to keep the beam depth down and avoid a bulkhead) cos you'd need 2 x 100mm bearings right next to each other - physical reasons rather than load reasons

OK, didn't realise you'd get another metre out and still have an acceptable slope on the roof TBH, so that's good to know. If I went another metre out, it may give the space to put a utility room back in somewhere.

I think you'd struggle to get a decent pitch and get a flashing in below the window on at the top of the stairs which is lower than the others.

[Specialone]

If the divide wall between the lounge and larger ktichen was reconstructed and widened, you could have both beams supported from this to the outer walls.



I only think you'd need a pier if you were trying to support two beams off an internal wall (in order to keep the beam depth down and avoid a bulkhead) cos you'd need 2 x 100mm bearings right next to each other - physical reasons rather than load reasons



I think you'd struggle to get a decent pitch and get a flashing in below the window on at the top of the stairs which is lower than the others.


Thats why i suggested reconstructing the dividing wall.

With regards to the pitch, its tight but i think you'd just get one, something the designer can check anyway before submitting, ive only got a 15 degree pitch on my own kitchen extension.

[Roberrrrt]

With regards to the pitch, its tight but i think you'd just get one, something the designer can check anyway before submitting, ive only got a 15 degree pitch on my own kitchen extension.

Depends on roof covering - different tiles / slates and different manufacturers have different minimum pitches. Think the most shallow I've spec'd is a 15 degree.

[Specialone]

Depends on roof covering - different tiles / slates and different manufacturers have different minimum pitches. Think the most shallow I've spec'd is a 15 degree.

I know mate, I've used pan tiles suitable for 12.5 degree pitch, I told ralph last night by pm that it depends on the tile, you can also overlap them a touch more.

Marley mods are one if the most common for lower pitch roofs.

[454697819]

yes you will be able to,

contact me if you want to know more details about how to get started.

[-Ralph-]

So what's the difference between an RSJ and a beam guys?

[Specialone]

Rsj's are sometimes referred to as 'I' beams and then beams.

[MisterTommyH]

So what's the difference between an RSJ and a beam guys?

RSJs are no longer produced in the UK - they are an obsolete section.

Common sections rolled in the UK are Universal Beams (UB) or Universal Columns (UC) - both can act as beams.

Easy way to spot them: An RSJ will have a taper on the inside of a flange. UBs and UCs have the inside of the flange parallel with the top/bottom depending on which you're looking at.

[Specialone]

You sure about that tommy?

That's something I didn't know, I know about the U beams as that's what's specced on calcs but didn't know rsjs weren't produced anymore.

Everyone calls them the same anyway, us workers do anyhow ;)

[MisterTommyH]

They're not in the TATA 'blue book', or on the web site or BS5950.

They're also not in any of the design software we use.

RSJ is a colloquialism thats stuck around - like people still refer to compo.

Not saying you couldn't get an RSJ as a special or reclaimed, but why would you when universal sections are more efficient.

[-Ralph-]

Met the neighbours yesterday, this is what they have done

http://i227.photobucket.com/albums/dd82/colinbal4/Hawthorne/FloorPlanGroundExtended4.png

No additional beams required, just three walls and a roof?

http://i227.photobucket.com/albums/dd82/colinbal4/Hawthorne/VisioExtended4.jpg

This is basically just to allow us dining space in the kitchen or lounge (or both), so we can use the 'dining room' for something else.

Why didn't you guys think of that?? ;-) :lol:

[Specialone]

That protudes further into garden and it's less additional footage than what you first spoke about, jeez, some customers ;)

[MisterTommyH]

http://i815.photobucket.com/albums/zz78/Thomas_Nathaniel_Hender/166989_10150718520083345_838898344_12361824_407803 201_n.jpg

Looks a bit like the GF part of what we've just done at a mates house.

Issues with this: I'm guessing from the velux's that you'd be looking to create a vaulted ceiling rather than a standard flat ceiling with light wells (you wouldn't get the advantage of the openings that way).

That being the case you couldn't use trusses so would have to build it in loose cut rafters (not a problem in itself). But to avoid eaves spread you'd need a ridge beam (had this as a requirement from bldg regs on the pictured one). That's an extra steel. The existing steel over the kitchen would need to be checked for a new point load at mid span (can't see that not working unless it was really small). Finally the lintel over the end window would need to be a bit more meaty than a standard lintel (the one pictured they put in a standard rather than what was specified and it visibly bowed so we have to come up with a bit of a Heath Robinson solution).

Can be done, it's just additional cost.

[Specialone]

Feck me Tom, your BCO's are straight out of training aint they, eaves spread on a roof that small?
What were the tiles made out of, lead?

If the wall plate is fastened securely then the eaves shouldnt spread on a tiny roof like that.
A semi vaulted ceiling, ie, have a higher ceiling but sloped sides wouldve also sorted that as the peak wouldve been braced.

I think things are done differently over you neck of the woods lol

Solihull bco's are a lot more realistic, id never get any work having to over spec everything like that, people are tight over this way as it is.

[MisterTommyH]

It was delegated to one of these consultancies.

The other way to do it is to use a higher tie like you say. Issue with that is that if you're trying to take restraint from the rafters to prove the wall you can't anymore.

Yoi're right for what ralphs looking at you probably wouldn't need a full submission, but we were more than doubling the footprint so they wanted a bit more. It's not what you know works. It's what you can prove by calc if you're asked to.

[-Ralph-]

OK, thanks for that Tommy.

I was thinking about natural light and space inside. The corner of the room next to the downstairs loo, would be quite dark. I could put another window in opposite the double doors and have a flat ceiling, but that window would be looking out onto a panel fence that would be about a metre away.

With the velux I could have an archway separating kitchen from dining area, and the dining area could have the high sloped ceiling.

[-Ralph-]

OK, you guys have posted whilst I was half typing, half watching the telly, thanks

What's a semi vaulted ceiling? Is that where you have an 'A' frame with a cross bar nearer the top and a flat section in the middle of the ceiling just above the top of the velux?

[MisterTommyH]

That's pretty much it. For something like that you'd be best to try and get someone like truss-form to do it.

[-Ralph-]

OK, like this

http://www.baysoft-web.co.uk/bsImages/PropertyImages/169_202_73_2_WEB.JPG

[Specialone]

It was delegated to one of these consultancies.

The other way to do it is to use a higher tie like you say. Issue with that is that if you're trying to take restraint from the rafters to prove the wall you can't anymore.

Yoi're right for what ralphs looking at you probably wouldn't need a full submission, but we were more than doubling the footprint so they wanted a bit more. It's not what you know works. It's what you can prove by calc if you're asked to.

Very true, i found in my experience, the difference between BCO's is massive, ive had some spend 20 seconds on site and seen what we wanna do and gone yes thats great, call me back for the next stage, then others have spent 30 mins explaining why they wanted 3 rows of noggins on a ceiling ( which i didnt do as it happens as i wasnt gonna be told by a 21year old kid fresh out of school how to do my job).

I explained the situation to the inspector who came next time and he said 1 row one would be enough.

My point is, they are sometimes really anal about stupid stuff then things you expect problems with, they sail them through.

[Specialone]

That's pretty much it. For something like that you'd be best to try and get someone like truss-form to do it.

Tbh Tom thats pretty much easy enough to cut on site, manufactured trusses arent cheap.

Give me 4x2 and 6x2 any day.

Im not a massive fan of vaulted ceilings tbh, i hate the way the insulaton specs have gone through the roof (pun intended), you have to go nuts now on extratherm now.

Its also a bigger volume of room to heat.

Cant you just put larger velux windows in?
I put one 4x3 window in a 11m x 3.5m rear extension a few years ago and couldnt believe how much light the room had.