What is a fair price for a loft conversion in 2018?

A loft conversion is a great way to add get extra space in your home without the hassle and expense of moving. It is often a more cost-effective solution than other kinds of extension, too. Many loft extensions do not need planning permission which makes them a simpler way to add space and value to your home.

In 2016 a survey by the Nationwide Building Society showed that converting a loft can increase the property’s value by up to 20%. In addition, they can make your home easier to sell. But what is more important is that they allow you to make the most of your home and create a brand new room or rooms full of light.

So, what do you need to consider and how much is it likely to cost to add a loft conversion to your home

Read on to find out the decisions you need to make, the options available, the legal processes required and the approximate costs of different types of conversion.

The type of loft conversion you choose will depend on your requirements and the structure of your home.

Is your home suitable for a loft conversion?

The first thing to do is to measure the headroom in your loft space. The bare minimum required for a basic conversion is 2.3 metres. For a simple conversion without dormers, you will need a height of 2.5 metres. If the headroom is lower than this, then more structural work will need to be done to create a new loft room and this will be more expensive.

The next section will give you an idea of the options available and their approximate costs.

The types of loft conversion available

  • Velux – The simplest and least expensive option is to create your new room by adding one or two Velux windows to let in light. The cost of this type of conversion is in the region of £20,000 -£25,000. It can only be done where the head height is 2.5 metres.
  • Dormer – A dormer is a small, flat-roofed extension with a window. Often two dormers are installed to create a nice symmetry. These allow in light and add headroom. Expect to pay between £25 – £30,00 for a standard dormer conversion. This type of conversion is suitable for lofts with a headroom as low as 2.3 metres.
  • Hip to gable – A hip-to-gable loft conversion involves developing the sloping roof of a property into a new vertical gable wall. This makes the sloping part of the roof the same height as the rest of the room and gives you plenty of internal headroom. It is not possible to do this type of conversion on a terraced house as there is no gable end. This is a more complex building project and will cost around £42,000- £48,000. However, it will give you more usable space than the previous styles.
  • Mansard – A Mansard extension involves replacing one whole side of the roof to form a straight wall and flat roof. The renovation is major and would involve planning permission. Costs would be in the region of £45,000-£50,000 for this type of conversion but it will significantly increase your living space.

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Planning permission

Around 75% of loft conversions come within the rules of permitted development and do not require planning permission. For example; a typical semi-detached house with plans for a rear dormer and front aspect roof window would not require permission.

However, if you are increasing the overall height of the roof or affecting the view of your neighbours then you will require planning permission. You will also need permission if your home is listed or in a conservation area.

Building Regulations

All aspects of the work must meet current building regulations and be signed off at various stages throughout the work. You should contact your local authority for further information.

A basic loft conversion will involve:

  • Reinforcing the floor
  • Installing skylights
  • Adding insulation
  • Fitting a staircase
  • Electrics, lighting and heating
  • Fire safety measures such as fire doors and smoke alarms.

More complex types of conversion will require considerably more work.

How long will it take?

The simplest loft conversion involving only Velux windows will take around a month to complete. A conversion with dormer windows will take approximately six weeks. A hip to gable or mansard conversion will usually be completed in around two months.

Additional costs to consider include:

  • For complex builds, you may need to pay an architect or engineer to produce plans
  • If you live in a townhouse, more scaffolding will be required so this will increase the cost
  • Slate roofs tend to cost more to convert than those with concrete tiles
  • The amount of work required within the house can affect the final costs. For example, if you need to redesign the space downstairs to accommodate
  • stairs to the new floor
  • If you are planning an en suite this will add to the final cost
  • Additional work such as fitted storage, painting and decorating and bathroom fittings will add to the expenses
  • Homes built after the 1960’s may need additional support due to the building techniques used and this can add to the cost

While planning a loft conversion can seem confusing they can actually be done quite simply. A basic loft conversion can be a cost-effective way of adding space to your home and creating additional bedrooms and bathrooms or rooms to accommodate whatever you require. As always, plan your project well, get expert advice on anything on which you are not sure, and only proceed with professionals that you trust.