Wrap Around Single Extension

[Barlows]

I'm currently considering extending our house on the ground floor.

I've drawn up some plans (at about 75% at the moment - see below) of how i would like it.

I'm a bit restricted with height by the first floor rear windows (bottom of window 3750mm from ground level, 3600mm from DPC) but i would like to extend out 4m from the rear which results in a pitch of 15°.

Due to the neighbour consultation scheme, i assume 4m would be acceptable on an attached house, can anyone advise if i'm being naive with this? I will be submitting full planning permission as from what i've read wrap arounds are not covered under permitted development. Can anyone advise if this is so or could i get away with neighbour consultation scheme for rear + permitted development for side?

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• Barlows
• 26 Jul 2013
• 1

Plus, any constructive criticism of my first drawing attempt would be appreciated!

Thanks,

 

[tony1851]

If you are confident no neighbour would complain, you could try the 4m extension across the rear under the notification scheme. But you would still need planning permission for the side bit because it would extend rearwards more than 3m beyond the original rear wall.

 

[freddiemercurystwin]

Watch that roof pitch as you are very limited with the choice of roof tiles.

 

[Barlows]

If you are confident no neighbour would complain, you could try the 4m extension across the rear under the notification scheme. But you would still need planning permission for the side bit because it would extend rearwards more than 3m beyond the original rear wall.

I'm pretty sure my neighbours wouldn't object, but i'd run it past them first to make sure.

So would i do 2 different applications or to save the hassle put it all through as 1 full planning permission?

Thanks,

Watch that roof pitch as you are very limited with the choice of roof tiles.

It's on a new build estate and a neighbour has built an 8m deep garage to the side of their house very similar to mine, that has a 15° roof and has the same tiles as existing so there should be something available to me

It's the eaves details that's concerning me as i'm not that familiar with it, for example, would the below be correct? *puts on flame suit*

View media item 64213
I've gone into this detail to see the pitch was >15°

Thanks,

 

[freddiemercurystwin]

Put it all under one application, explain in a covering letter or supporting statement that part of it is PD.

Just because your neighbour has done it does not necessarily mean you will be able to. Investigate the tiles now, there have been many a thread on this forum whereby Building Control has refused a particular tile for a low pitch roof as it was below the manufacturers quoted minimum pitch.

 

[Barlows]

Put it all under one application, explain in a covering letter or supporting statement that part of it is PD.

Just because your neighbour has done it does not necessarily mean you will be able to. Investigate the tiles now, there have been many a thread on this forum whereby Building Control has refused a particular tile for a low pitch roof as it was below the manufacturers quoted minimum pitch.

Will do, my LPA has approved a few extensions lately on our estate without question so hopefully i should be ok. I have a sewer easement where the proposed extension is but United Utilities gave me a provisional OK so i can submit plans and arrange a build over agreement.

I'll speak to my neighbour and find out exactly what the tile is and make reference to it in my planning application, or even run it by the BCO before i submit.

I'm not up to speed with roofing, but my neighbour used trusses as it was purely on the side and not extending past the rear wall. Would i be ok with rafters, wall plate and ridge board, or is that a question for the roofing forum?

Thanks,

 

[tony1851]

(As above re. planning).

On the eaves sketch, I suspect your lintel is too shallow for the span of the patio doors.
Yes, you will have to watch the roof pitch. If you are going to have rooflights
(which might be necessary on that length of extension) you will be limited to a 15 deg. pitch.

 

[Barlows]

(As above re. planning).

On the eaves sketch, I suspect your lintel is too shallow for the span of the patio doors.
Yes, you will have to watch the roof pitch. If you are going to have rooflights
(which might be necessary on that length of extension) you will be limited to a 15 deg. pitch.

Thanks, to be honest i think i've left a CGE90/100 "eaves linel" on the drawing, i'll have to change it to a standard CG90/100 which is a bit higher. That'll affect the size of the block on the inner wall, up to ~100mm from 65mm. Every mm is counting at the moment to try and keep the pitch up!

That's why i'm trying to stick to 15° so i can fit velux windows ok.

Thanks,

 

[freddiemercurystwin]

Or you can just raise the ridge/pitch and you detail a little flat roof beneath each window. Its a pretty common workaround.

 

[tony1851]

By a bit of judicious working, you can also slim down the raftrs. Don't just take the size from the tables - they're generally very conservative.

 

[Barlows]

Or you can just raise the ridge/pitch and you detail a little flat roof beneath each window. Its a pretty common workaround.

Yeah i understand, that was my other option which i was trying to avoid but was willing to turn to if absolutely necessary!

(I've been trying to find a picture as an example on google for the last 10 mins but can't find the right term to search for)

 

[Barlows]

By a bit of judicious working, you can also slim down the raftrs. Don't just take the size from the tables - they're generally very conservative.

As the span is approx 4.3m, off the top of my head, the size i got from the table was 200x63?

 

[freddiemercurystwin]

Courtesy of woodplops

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• ^woody^
• 20 Jan 2012
• 5

I think I've got a photo of one somewhere, try and dig it out.

 

[tony1851]

As the span is approx 4.3m, off the top of my head, the size i got from the table was 200x63?

Too big.
TRADA tables are conservative. On that span you could easily get down to 7x2s if at slightly closer centres than 400.
If it helps to save a bit of height, you can also birdsmouth deeper at the eaves - the bending stress is not critical here.
Have you thought of putting a steel purlin across running side-to-side? That way you could split the span and get down to 5x2s.

 

[Barlows]

As the span is approx 4.3m, off the top of my head, the size i got from the table was 200x63?

Too big.
TRADA tables are conservative. On that span you could easily get down to 7x2s if at slightly closer centres than 400.
If it helps to save a bit of height, you can also birdsmouth deeper at the eaves - the bending stress is not critical here.
Have you thought of putting a steel purlin across running side-to-side? That way you could split the span and get down to 5x2s.

Thanks for your reply, sorry for only just getting back to you.

A steel purlin running side to side would definitely be an option, i assume this would take up an extra ~70mm depth to the roof (ie, vaulted ceiling level lower)

Are 8m lengths easily available?

I think i've been measuring the span wrong, from wall plate to wall plate is more like 4m.