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Putney Loft Conversions

What loft conversions and extensions are possible in Putney and advice on how do get permission and the likely costs.

Putney Loft Conversion Cost

Due to the pitch of the sloping roof, you often can’t add as much usable area while keeping within the existing footprint as a basement conversion or extension, but the project will generally turn out to be much cheaper, faster, and cleaner to complete - this much lower cost in turn makes for highest return on investment. Creating a new roof in the roof also avoids the main issue of a typical side or rear extension, because you don’t lose any of your precious outdoor space, which is often already limited in a Putney house. As a rule of thumb, the overall cost of a loft conversion in this part of the capital will range from £50,000 for the more simple to over £100,000 for larger schemes or those with a more high-end finish. A simple internal conversion done yourself can be achieved for as little as £20,000 depending on how much of the work you feel competent enough to undertake. At AC Architects we are often asked to price the whole project after obtaining planning permission, and we have a little black book of the most reliable local tradesmen so we can help you get quotes from builders who we have experience of doing a great job.

Putney Loft Extension Regulations The easiest and fastest way to create a bedroom in your attic space is to stay within the Permitted Development rules for a loft conversion, which essentially ensures the building keeps the same external appearance at the front of the house and does not exceed the original roof space by more than 40 cubic metres for a terrace house or 50 cubic metres for other houses. You will also need to be careful not to exceed the height of the original roof and you can’t add or alter extra elements such as chimneys, balconies, whilst any side facing windows need to use obscured glass. There are lots of other detailed restrictions and permitted development does not apply to roof extensions in a conservation area, or to flats anywhere, even when these are in what used to be a house, so most property owners work through the planning process with an architect familiar with the rules and local interpretation of them. Any building works on this scale also need to comply with the Building Regulations. Do I need a Certificate of Lawfulness for a Putney Loft? While it is usually not essential to obtain a CoL if your loft is Permitted Development, you may find it hard to later sell your property without one, as this little piece of paper proves that the work on your property is lawful. Building Regulations consent is always needed and is separate from a CoL. How Long does a Loft Extension take? A standard loft conversion will usually take between 4 and 8 weeks to complete, depending on the design and finishes you choose. A simple rear dormer on a terrace house will be quicker than if you’re adding a gable end as well to a semi or detached house, or raising shared party walls, but may not be as spacious. The good news is that most of this work doesn’t interrupt your use of the house below. What is the minimum height for a loft conversion? There are many opinions on this, but most people consider the minimum comfortable ceiling height (i.e. measuring from attic floor to the tallest part of the roof) to be at least 2.2 metres. To allow for a properly insulated roof and the new floor construction that means you need to start with 2.5m from the ceiling timbers to the tallest point inside the roof. If you have less, there are ways around this, including lowering the ceiling of rooms below, but remember this begins to increase the cost too. Some boroughs, including Wandsworth, will often allow the roof to be raised by, say 300mm, but this needs Full Planning Permission. What does an architect cost to design a loft conversion? While this will always depend on the scale and complexity of your project, a general rule of thumb would be to budget between £3,000 and £6,000 for an architect to design for you. Additional costs might include the planning application (if one is needed), Party Wall Act agreements with your neighbours, the creation of a builder’s plan and putting your project out to tender. Doing this process with a local architect vastly improves your chances of finding contractors that are good value, reliable and produce a high standard of work, because the local architect has much more experience of which are the good and which the not so good to work with in your area. Can my Loft be classed as a Bedroom in Putney? The short answer is yes, but only if the conversion is done in compliance with building regulations. Your architect will advise you on the extra specifications needed, including insulation, head height and fire safety, if you want to be able to increase the number of bedrooms appearing in the estate agent’s window. If you want the property to be valued with the extra space as bedroom(s) the conversion needs to be signed off fully regulation compliant as such. The extra property value and comfort created by having more bedrooms tends to mean the extra cost of fully meeting the regulations is well worth it.


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