extension estimate

twinkleT · 31-01-2015 10:32pm #1

hi all,

I was wondering if someone could give me a rough guide as to what we'd pay to extend the back of our house.
We already have an extension, my hope is that we would extend it out to the patio door in pic 1 with basically just 2 windows at right angles.
We'd also like to knock out the back wall about 8 ft ( currently where the window is ) to bring it into the main house.
I've attached an example of the finish ( but we dont really want the windows to open )

all comments appreciated thanks

twinkleT · 31-01-2015 10:33pm

i cant seem to add the pics sorry !

twinkleT · 31-01-2015 10:37pm

cant edit either - basically I am looking to square off a right angle corner with 2 glass panels at right angles 8ft * 8ft with a flat roof !

Gumbo · 01-02-2015 2:06am

twinkleT wrote: »

cant edit either - basically I am looking to square off a right angle corner with 2 glass panels at right angles 8ft * 8ft with a flat roof !

10k give or take?

RobAMerc · 01-02-2015 7:24pm

thanks kceire - twinklet is my mrs she was trying to upload these.

we had planned to open the whole back of the house up and build right across, but it looks as if its gonna be a bit too pricey for us.

An alternative is to do this, therefore bringing the current extension into the house. We had been told we could do an 8ft opening ( where the window is now ) without a huge RSJ. ( you might be able to confirm that. )

thanks again.

btw - what we would be building would be no where near as big or as impressive looking as that one, nor do we want it to open.

Calahonda52 · 01-02-2015 10:03pm

A his and hers post!
Couple of things.
AFAIK strictly speaking u need planning vfor this second extn but as the firstvone will disappear. ........
U will need a steel column beside the patio door as well as at the oth end to take the RSJ but its all doable.
U need to relocate the shore and sort out the damp walls.
As it look this is north facing, maybe a velux or 2 to throw light back into house

Gumbo · 01-02-2015 10:28pm

RobAMerc wrote: »

thanks kceire - twinklet is my mrs she was trying to upload these.

we had planned to open the whole back of the house up and build right across, but it looks as if its gonna be a bit too pricey for us.

An alternative is to do this, therefore bringing the current extension into the house. We had been told we could do an 8ft opening ( where the window is now ) without a huge RSJ. ( you might be able to confirm that. )

thanks again.

btw - what we would be building would be no where near as big or as impressive looking as that one, nor do we want it to open.

The max span an off the shelf lintel can go is 3m so yes, you could do 2.4m (8Ft) and 300mm bearing each side without an RSJ. Anything above that needs to be designed so most engineers will rough in an RSJ.

RobAMerc · 01-02-2015 10:43pm

Calahonda52 wrote: »

U will need a steel column beside the patio door as well as at the oth end to take the RSJ but its all doable.

So it does need an RSJ ?

Calahonda52 wrote: »

As it look this is north facing, maybe a velux or 2 to throw light back into house

It is west facing - would the 2 window "walls" not throw enough light in ?
Although a velux would be good alright.

RobAMerc · 01-02-2015 10:44pm

kceire wrote: »

The max span an off the shelf lintel can go is 3m so yes, you could do 2.4m (8Ft) and 300mm bearing each side without an RSJ. Anything above that needs to be designed so most engineers will rough in an RSJ.

So it doesn't need an RSJ ?

Are we still looking at 10k ?

Calahonda52 · 01-02-2015 11:30pm

RobAMerc wrote: »

So it does need an RSJ ?

It is west facing - would the 2 window "walls" not throw enough light in ?
Although a velux would be good alright.

Looks very damp for west facing.
I see the deck chair but is that for effect:)

Re RSJ.
You will need something to support the wall above so RSJ or something, dont know what kc means by lintel, but it will need something so don't get hung up on if its a RSJ or lintel.
Re wall windows, no re throwing light into room behind.
Look at planning app FS5/010/14 on fingal co co website, they went with custom velux

RobAMerc · 02-02-2015 12:06am

thanks guys

The one does look like what we are after alright.

I see what you mean (Calahonda) about light, although I had thought removing the back wall of the kitchen would let more in, I think adding a roof light might be a worthwhile option.

Any idea on what we'd spend on the proposed ?

Gumbo · 02-02-2015 2:04pm

Calahonda52 wrote: »

dont know what kc means by lintel,

A lintel van be something other than an RSJ/Steel Beam.
Basically any ope in a wall over 3m span needs to be "designed", so engineer involvement. A typical 2.4m span (like the OP), a suitable lintel can be bought from the suppliers/Keystone etc and used without any engineer involvement.

http://keystonelintels.com/?gclid=CN-Ti7ipw8MCFWJ22wodKx0AXg

Calahonda52 · 02-02-2015 3:01pm

kc, thanks for this.
In passing where is the 3.00m "rule" described? Want to learn here

I just called them and they suggested this one:
http://keystonelintels.com/lintels/standard-lintels/100mm-inner-leaf-100mm-outer-leaf-lintels/extreme-load-lintels/
for retro fitting as most of the other ones are not designed for retro in opes being preped as envisaged.
Most of them have a up stand in the middle which mitigates against being inserted into an ope that is being done as proposed

It is in fact an RSJ on the inner leaf

If the wall is a cavity wall then the support must be wide enough.

However, all doable

Gumbo · 02-02-2015 3:58pm

Calahonda52 wrote: »

kc, thanks for this.
In passing where is the 3.00m "rule" described? Want to learn here

Technical Guidance Document Part A, Section 1.1.3.19
&
Homebond

Calahonda52 · 02-02-2015 4:30pm

kceire wrote: »

Technical Guidance Document Part A, Section 1.1.3.19
&
Homebond

Much obliged. Thank you.

extension estimate

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