Rear two story extension and loft dormer

Firstly you would be advised to understand the correct terminologies: Your Loft conversion/ dormer is the exisiting second floor extension. I am understanding that you want to build over a ground floor extension to create a first floor extension. Such things are why the Planning System exists. If you want to work within permitted development guidelines then things are bit more restrictive. However a full planning application offers the maximum potential for expansion and it should simply be a matter of taking advice from your architect or tech. or other person preparing your application drawings. Good luck

In principle, adding a second storey above an existing single-storey rear should be acceptable, but will depend on a few key planning considerations rather than a simple yes or no. The main factors the council will look at are the overall depth and massing of the rear elevation, how the additional storey would relate to the existing house and neighbouring properties, and whether it would result in overlooking, loss of light, or an over-dominant form, particularly given there is already a rear dormer in place. Where a property already benefits from a rear extension and roof alteration, councils are usually more sensitive to the cumulative impact of further additions, so proportion and restraint become critical. That said, where a second storey is carefully designed to sit comfortably within the existing footprint, respects neighbouring windows and boundaries, and reads as a coherent part of the house rather than an obvious add-on, it will be better justified from a planning perspective. The key is shaping the proposal correctly from the outset, rather than simply stacking another floor on top of what’s there.

It is achievable, provided the design complies with two general requirements: 1. A 45-degree daylight rule; and 2. Avoiding overlooking into the neighbours’ property or garden. I hope this clarifies.

Hi Alex, Generally speaking adding a second storey to your rear extension will require Planning Permission. 2 Storey Extensions to the rear can be tricky - mainly due to overlooking and impact to neighbours amenity and privacy. This is very generic guidance though and I would recommend speaking to a local Architect (We usually offer a free site visit to determine Planning constraints before committing to any fees). The 45 degree line rule is again very generic and not a rule as such, more guidance from Planning. This refers to drawing a 45 degree line from your nearest neighbours habitable window (bedrooms not bathrooms). The 2 storey extension will likely need to avoid the area within this line - However every project is different and needs assessing on its own merits. For example, if a neighbour or property on your street has done something similar it can set a president that yours would be accepted. I have had this recently where the Extension encroached into the 45 degree line, however as a neighbour 5 doors down had already done this, the Planning was accepted. It also largely depends on position and sun path. Hopefully this helps! Tom

Not necessarily, probably require a trial hole to assess existing footing, suitability to carry a second storey and load. It's possible to construct 2nd storey walls in timber, clad with timber, tile or cement or composite board. If there is a precedent locally you have a better chance of approval. Hope this helps, Phil.