Retaining wall question

[jimnich]

New to the forum so apologies if this has been covered elsewhere. I am planning to build (or have built, more accurately) a dwarf wall conservatory onto the side of my bungalow. So far so good, a well trodden path where there is a multitude of information to get me through the project. However, I have one of those bungalows that is built on a slope where the garage forms the base below much of the structure. The conservatory will encroach partly into the sloping ground side of the house, so that part of the dwarf wall will have to be built on the solid ground level with the base of the garage (as I'm aware I can't build on infill). So, my question is this, does this dwarf wall now constitute a retaining wall, and if it does (it'll be well over 1.2m so requiring design by a structural engineer) does anyone have some rough figures that an engineer will charge to design it.

Thanks for any help.

 

[DevilDamo]

Engineers would normally work on an hourly rate, so it can vary. Just approach a few, obtain quotes and go from there. Something like that may take 2-3 hours so I would say min. £150 + VAT would be a good starting point.

 

[jimnich]

Thanks DOH, I was worried the design alone (and I intend to use the existing retaining wall at the back of the garage as a template) could be prohibitively expensive.

As an aside, I went and saw the Building Standards chappie today and he confirmed that yes, it constituted a retaining wall, but the retaining element would only need to be as high as the backfill behind it (approx. 1.5m I reckon) so it may not need to be as hefty a structure as I initially feared.