Top Three Ways To Add Value To Your Property

In this article we explore the top 3 ways to start adding value to your home by 7 to 15% or more. As you’d expect, most of them involve conversions of one sort or another and building work but have been proven to increase both desirability and overall property value.
adding value to your home

Adding Value To Your Home – Basement Extension

It’s hardly surprising that in space-poor London, people have been getting ever more creative in finding ways to extend the square meterage of their properties. Digging down has become the latest craze in home improvements with some people managing to double the size of their property by adding an additional two stories beneath the ground. They can provide additional living space and given the underground nature of that space can make for excellent home cinemas, spas, gyms, swimming pools and games rooms.

The basement extension companies often state that a good conversion can add up to 15% to the value of the property and it’s the most popular form of home extension in central London ‘hot spots’ such as Notting Hill.

Is it worth doing?

The first step is to check with your local estate agent that doing a basement conversion will work in adding value to your home, but with property values so high in central London, it’s likely that almost any type of basement build will be financially viable.

The first stage is to make sure that your property is suitable for basement excavation. Most problems can be overcome – but at a cost. So a full survey is the starting point. Things like high water tables, main services running beneath the property and being close to underground streams can make the costs prohibitive. Modern terraces and townhouses that are built on raft foundations can’t be underpinned, so it’s impossible to excavate a basement in these types of properties.

Examining every detail

Access is a consideration and the ability to get a JCB in to do the digging. Being too close to a boundary or road can cause problems. If this is an issue, then it can be possible to excavate by hand (and this has been done) but naturally it adds time and cost to the build and will limit the scale of the works being undertaken.

Modern technology now means that basements no longer run the risk of turning into dank, damp spaces over time. In the old days they would just be lined with cement, which would decay and start to leak. These days they are lined with a heavy waterproof membrane which is designed to have water run-off into a gulley and then into a water sump. This is then emptied by a pump which comes on when needed and can’t be heard from within the basement. Depending on the size of the area there may be a need for more than one pump. Pumps are serviced annually and can be fitted with a back-up power supply.

Planning Permission

If you are simply adapting an existing cellar and the work is internal, then you probably won’t need planning consents but will need to meet current Building Regulations. If you are starting from scratch, then you will need planning permission. If you share walls with neighbours, then you will need their written consent before you can begin any building work. If you are planning to dig down deeper than their own foundations, then you will also need their consent.

If you intend to use the basement for living space you will also need to include more than one fire escape, so you must have a window or a door. This should be factored into the design of the basement which will also typically include some kind of light well.

Councils are now starting to introduce new rules to curb over-ambitious projects and both Westminster and Kensington and Chelsea now say you can only go down one level and won’t be allowed to take up more than 50% of your garden space.


Each excavation is unique so costs vary enormously. Current estimates start around £400m2 plus VAT for a fully fitted space.

And if you go for it, you’ll be joining the ranks of Jemima Khan, Dave and Samantha Cameron and Andrew Lloyd Webber in creating an ‘iceberg’ home. Ricky Gervais added a basement gym and swimming pool to his Hampstead home which is claimed doubled the value of his property from £3.5m to around £7m in September 2015.

Adding Value To Your Home – Loft Conversions

If digging down doesn’t appeal, then going up may be the answer.

Depending on your roof structure different types of loft conversion are available, adding additional living space to your home. Rooms in the roof can make use of sunlight for most of the day and can have amazing character due to the shape of the roof.

Depending on the size of the conversion current estimates are that a loft conversion can add up to 12.5% to the value of your home.

Types of Conversion

There are three main types of loft conversions: the rooflight or velux option causes the least amount of disruption and just involves adding roof lights which are flush to the roof. The dormer extension creates extra headroom by creating a dormer window area. Finally there is the Mansard conversion. The roof space is extended with a box-like construction.

Mansard Conversions

Named after the 17th Century French architect, Francois Mansard, these conversions are an extension across the entire plan of your property’s roof and effectively add another storey to your house. They are mostly installed facing the rear of the property (away from the road), changing the sloping side of the roof to almost vertical side (with a pitch of 70-75 degrees). The roof is flat and windows are housed within small dormers. It is also possible to have a ‘double’ conversion where there is also a Mansard to the front of the house. This is usually not possible in most parts of London, although it can be negotiated depending on the location and type of house.

Mansards lofts are suitable for almost any type of home and are built by raising the party/gable walls either side of the house and then creating a timber frame for the roof.

Planning Permission

Planning permission is almost always required for this type of extension as they change the roof shape and structure. This will usually be handled by the company you choose to do the work and should be part of the quote they give you. If you live in a conservation area, you will be required to submit a design and access statement to explain the design concepts and show that potential issues have been identified and remedied.

If you have party walls, written consent from neighbours will also be required.

There are also Fire Regulation requirements with a third storey needing to be given half-hour fire protection.


If the existing roof is being replaced, then a conversion is an ideal opportunity to increase the insulation in the roof and become more energy efficient. It’s possible to fit a breathable roofing membrane which is waterproof but is air-permeable to allow ventilation to the roof structure. This ‘warm roof’ is very effective and planning consents usually allow for an increase in roof height to accommodate the insulation.

Existing gable walls will also need to be insulated to meet the Building Regulations.


It’s also worth taking this into account when planning a conversion. The Building Regulations standard is not very rigorous in this area, so do make sure that architects and builders have taken good soundproofing practice into account.

Sound can travel between the new attic floor and the rooms below in two ways: impact transfer and airborne transfer. The latter can be reduced by making sure the new build is airtight by doing things such as using sealant around floor edges and under skirting boards and floorboards. Minimising impact transfer (the sound of baby elephants dancing) can be achieved by filling the voids between floor joists with high-density acoustic insulation and using high-density chip board.


This is the key to a superb loft conversion. A well planned and placed staircase is the main means by which the loft conversion becomes part of the house. It’s also essential to make sure that not too much of the storey below is lost to create access. It will need to be at least large enough to get furniture into the new area.


Adding a bathroom and/or shower room to the loft conversion adds additional value to the conversion. To do this you need to think about the location of existing water and waste services, but usually it’s possible to overcome any issues using flexible plastic plumbing.


Naturally this depends on the size and complexity of the intended conversion. Mansard conversions are the most expensive and a typical cost for a Victorian house is around £60,000.

Adding an Orangery or a Conservatory

If space permits, adding a conservatory or orangery is a great way to integrate outside space with inside and add interesting living space. Traditionally a conservatory is mainly glass, but if you want more of a garden room, then going for an orangery with internal walls could be the answer. Conservatories can also be used to house indoor swimming pools.

It’s estimated that a conservatory can add about 7% to the value of your property with a full scale extension adding around 11%.

Planning Permission

There are limits to the size of the conservatory under planning regulations. No more than half the area of land around the ‘original house’ – which means as the house was first built or as it stood on 1 July 1948 – can be covered by additions.

Until recently the limit on the size of a conservatory was 4m past the end of your house, but this has now been changed to 8m for detached homes and 6m for other housing. For the new additional space, you will need to follow a new and different process. Your conservatory builders can advise you.

If you manage to comply with the conditions set out in the governments planning portal, then you will be able to get away with not needing planning permission.

Adding Value to your home

For a conservatory to add value to your house you need to make sure that it fulfils some basic criteria.

It’s in keeping with your home

It’s essential that it doesn’t look like a tacked on ‘bubble’ to the wall of your house. The design should look aesthetically pleasing, tone in with the rest of your house (windows and building materials) and be designed so that if ‘flows’ with the rest of the house. As a space that is intended to be ‘half-way’ between house and garden, it’s essential that it doesn’t just become a corridor into the garden. Don’t make it seem like a separate building with its own entrance and make sure it is fitted out the highest standards.

It lets in the right amount of light

Depending on its position and type of build, it will let in different amounts of light. Make sure this appropriate for the use you intend it for. No one wants to spend time in a harshly bright glass bubble overlooked by neighbours.

It has a high energy rating to reduce bills

The WER rating of the glass and the air-tightness of the fittings are essential considerations, but do make sure that it will also be a pleasant and comfortable place to sit by ensuring adequate ventilation which will also cut down on condensation – the bane of poorly built conservatories.


Again this depends on size and build. The cost typically ranges from £5,000 to £30,000. A full-blown extension usually comes in around £10,000 to £40,000 again depending on the size and styling.


These are currently the most popular ideas for adding value to your home in London at the moment. As with all things, doing proper research and planning to ensure that your intended investment will bring dividends is essential – so do check with us that your plans will indeed bring the increased property value you are hoping for.
If you plan to go ahead with adding value to your home make sure you avoid the most common property development mistakes from the outset.
“The Information on this site is provided for information purposes only. The Information is not intended to be and does not constitute financial advice or any other advice.”


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