TIMBER/BLOCK/SIPS DOUBLE GARAGE INSANE £££

[oliwoodings]

Ah okay makes a bit more sense! I'm still a bit confused about where these 150mm upstands are in your drawings though - in the last picture have you removed the outer block skin?

 

 

[saveasteading]

2 hours ago, Saul said:

the upstands don’t count as Roof Height

Why ever not? I hadn't heard of this and planning is usually about the external dimensions. 

I don't think you answered why you need the upstand.

[Saul]

9 hours ago, saveasteading said:

Why ever not? I hadn't heard of this and planning is usually about the external dimensions. 

I don't think you answered why you need the upstand.

Upstand requirements for flat roof design

IKO TEAM

09/01/2022

A frequently posed question when designing flat roofs is “What upstand height do I need?”

On the face of it a simple question with, one may think, a simple answer. Most of the time the simple answer is “150mm above the finished roof level”. We may give that advice but unless we probe further can we be sure that the advice is fully understood and correctly interpreted? In our experience, not always.

BS 6229:2003 ‘Flat roofs with continuously supported coverings Code of Practice’ and BS 8217:2005‘Reinforced bitumen membranes for roofing Code of Practice’ both state that if unwanted water ingress into the building is to be avoided all weatherproofing upstands occurring around the roof area; (which would include abutments, rooflights and service vents etc) must have a minimum height of 150mm.

[oliwoodings]

That doesn't say anything about the 2.5m height restriction though. What advice have you found that states you don't need to include the 150mm upstand inside the 2.5m?

[saveasteading]

It doesn't say that you need an upstand, only that any upstand you have  sbould be 150mm min.

[Saul]

16 hours ago, saveasteading said:

Why ever not? I hadn't heard of this and planning is usually about the external dimensions. 

I don't think you answered why you need the upstand.

architect says that the eaves height of a flat roof is measured at top of roof, ignoring the parapet which would sit above the top of the roof

 

 

 

[Saul]

16 hours ago, saveasteading said:

Why ever not? I hadn't heard of this and planning is usually about the external dimensions. 

I don't think you answered why you need the upstand.

architect says that the eaves height of a flat roof is measured at top of roof, ignoring the parapet which would sit above the top of the roof

from the Government Website http://data.parliament.uk/DepositedPapers/Files/DEP2012-1435/Parapets.pdf

 

For the purpose of measuring height, the eaves of a house are the point where the lowest point of a roof slope, or a flat roof, meets the outside wall.
The height of the eaves will be measured from the ground level at the base of the external wall of the extension to the point where the external wall would meet (if projected upwards) the upper surface of the roof slope. Parapet walls and overhanging parts of eaves should not be included in any calculation of eaves height.

 

 

 

Edited April 4 by Saul

[saveasteading]

1 hour ago, Saul said:

Parapet walls and overhanging parts of eaves should not be included in any calculation of eaves height.

Well worth knowing.

[joe90]

Ditto, not heard that before (every day is a school day). Does seem mad tho, permitted development is there really to enable non intrusive buildings yet there appears to be no limit on the height of the upstand/parapet.🤷‍♂️

Edited April 4 by joe90

[Saul]

23 hours ago, oliwoodings said:

Ah okay makes a bit more sense! I'm still a bit confused about where these 150mm upstands are in your drawings though - in the last picture have you removed the outer block skin?

 

 

I didn’t draw the upstands. They would border around the front and sides 150m above the top of the front ferring but the back will be open to the gutter. Proper drawings are being done. This is just me playing on Sketchup. 

[oliwoodings]

6 hours ago, Saul said:

architect says that the eaves height of a flat roof is measured at top of roof, ignoring the parapet which would sit above the top of the roof

from the Government Website http://data.parliament.uk/DepositedPapers/Files/DEP2012-1435/Parapets.pdf

 

For the purpose of measuring height, the eaves of a house are the point where the lowest point of a roof slope, or a flat roof, meets the outside wall.
The height of the eaves will be measured from the ground level at the base of the external wall of the extension to the point where the external wall would meet (if projected upwards) the upper surface of the roof slope. Parapet walls and overhanging parts of eaves should not be included in any calculation of eaves height.

 

 

 

 

If you've got an architect, why aren't they just giving you a design that fits within the 2.5m restriction?

Edited April 4 by oliwoodings

[Saul]

On 04/04/2024 at 22:28, oliwoodings said:

 

If you've got an architect, why aren't they just giving you a design that fits within the 2.5m restriction?

it wasn't my architect and didn't think you'd need one for a simple garage. Have now got a designer working on it which is costing £600 that I'd hoped not to spend.