Proposed conservatory - height of DPC

[GoferBlue1947]

I have a problem! We would like to fit (DIY) a conventional lean-to conservatory to our bungalow, outside the existing French doors which lead to the patio. The problem is, is that there is not enough height to the fascia board to give even the minimum fall required. We have looked at all manner of proposals - Edwardian hipped roof with box gutters etc. which is putting the cost out of our range.

In order to achieve the necessary fall I wonder is it possible to have the conservatory floor at a lower level than the bungalow floor and consequently also have the conservatory DPC level lower than the bungalow DPC level? This could be achieved by excavating the surrounding patio by about 150mm or so so we can claim that the DPC is still 150mm above the adjacent ground level. I know this means a step down into the conservatory but this could actually be a "feature" rather than a drawback IMO.

Also does ALL the surrounding ground have to be 150mm below the DPC or just that in the immediate vicinity - maybe say not less than 300mm from the wall for example?

Many thanks for any thoughts/ideas.

 

[tony1851]

The purpose of having the dpc 150 above ground level is to prevent rainwater from hitting the ground and splashing up the wall above the dpc.

So if the ground was lowered for about 300 width around the extension, that would prevent splashing above the dpc and so would comply.

 

[GoferBlue1947]

The purpose of having the dpc 150 above ground level is to prevent rainwater from hitting the ground and splashing up the wall above the dpc.

So if the ground was lowered for about 300 width around the extension, that would prevent splashing above the dpc and so would comply.

Thanks Tony. This was my gut feeling but knowing how pernickity some BCOs can be, I did just wonder. My idea is to create a trench around the conservatory base and make a gravel bed with a length of plastic land drain buried therein which would run to a soakaway (which is already in existence). As it's only a conservatory anyway there shouldn't be an issue but I have seen a thread in this forum on the subject of conservatories and BCOs and it seems to be quite a controversial issue!

 

[Gazman16]

A double hipped roof with box gutter shouldn't be a huge price difference.

A couple of other options are:
1. Leanto roof with box gutter, http://www.diyconservatoryshop.co.uk/html/Ultraframe-Lean-To-Roof-With-Soffit-Box-Gutter.html Maybe combined with a 5 degree pitched roof.
2. a reverse leanto with box gutter like the forth pic on this page http://www.tradeconservatories2u.co.uk/conservatories/veranda-conservatories.htm

 

[GoferBlue1947]

A double hipped roof with box gutter shouldn't be a huge price difference.

A couple of other options are:
1. Leanto roof with box gutter, http://www.diyconservatoryshop.co.uk/html/Ultraframe-Lean-To-Roof-With-Soffit-Box-Gutter.html Maybe combined with a 5 degree pitched roof.
2. a reverse leanto with box gutter like the forth pic on this page http://www.tradeconservatories2u.co.uk/conservatories/veranda-conservatories.htm[/QUOTE]

Thanks for your input Gazman. I have found that even modest deviations from the "standard lean-to conservatory" start racking up the cost. The problem I have is not only the lack of height from the fascia board to the ground but also the fact that the conservatory will be breaking into a long run of guttering with a single downpipe at one end. It seems that it is impossible to connect a rear box gutter into my existing OG gutter due to the different heights. As it is I will have a problem with rain water coming off the conservatory roof itself - this will have to go to a primitive "soak-away" which I have made to drain the patio when we have heavy rain!

 

[GoferBlue1947]

Things have moved on a bit! I have discovered that more and more folk are opting for a low threshold entrance and not just for wheelchair users but for general convenience because the floor of the extension and the patio slabs are at the same level.

In the case of a conservatory it seems that it is possible to have a DPC at/just above ground level by using a linear channel type drain running along the base of the wall. This provides the magical 150mm distance below the DPC. I found this link on the web:

http://www.molevalley.gov.uk/CausewayDocList/DocServlet?ref=MO/2010/1529&docid=358063

which shows something similar. I could also use this same linear drain to take rainwater draining off the conservatory roof.

Any thoughts/comments much appreciated. Thanks.

Gofer

 

[GoferBlue1947]

Things have moved on a bit! I have discovered that more and more folk are opting for a low threshold entrance and not just for wheelchair users but for general convenience because the floor of the extension and the patio slabs are at the same level.

In the case of a conservatory it seems that it is possible to have a DPC at/just above ground level by using a linear channel type drain running along the base of the wall. This provides the magical 150mm distance below the DPC. I found this link on the web:

http://www.molevalley.gov.uk/CausewayDocList/DocServlet?ref=MO/2010/1529&docid=358063

which shows something similar. I could also use this same linear drain to take rainwater draining off the conservatory roof.

Any thoughts/comments much appreciated. Thanks.

Gofer

Am re-posting this in case anyone has any thoughts! Thanks.
Gofer