Extension Beginner’s Guide

There are lots of reasons why you need more space in your home. Maybe the family is expanding, or someone is coming to live with you. Perhaps you need more space to do the things you enjoy. Whatever the reason, the simplest answer to gaining more space is not to move to a new house but to extend your property. Here’s a beginner’s guide to the world of extensions.

Materials and construction types

One of the ways to choose an extension type is to look at the materials and construction types available and use this to give you some ideas. You can take three main approaches to the project – a self build extension, a builder led project or a hybrid where you do some yourself and leave other areas to tradesmen.

Glass box extensions include styles like conservatories where the space has a much larger percentage of glazing than a normal house.

Brick built

Standard brick built extensions are still a popular option. Once these featured a flat roof but now many have some pitch to the roof to avoid the perceived problems with flat roofs. They are built in materials similar to the main house and can be a single storey or two – even more if your property is more than three storeys high.

Timber frame

Timber frame construction has come back into fashion as people realise the ease of use of these kits and the level of insulation and energy efficiency you can get from constructing in this way. These are popular for the self build extension project because you can get kits where the timber frame is perfectly prepared for you.

Rapid masonry

Rapid masonry construction is a quick method of making an extension that uses lightweight block and a thin joint masonry system. It can see a single storey extension built in a day and doesn’t need to wait for mortar to become stable.

Modular extensions

Modular extensions are similar to the timber frame kids and come in various sizes and shapes, taking less than a week to put up and finish. This kind of kit includes the walls and timbers for a roof, so the rest of the building materials and work needs to be carried out as normal.

Glass box

Glass box extensions include styles like conservatories where the space has a much larger percentage of glazing than a normal house. This makes for very light and bright spaces but can be a little harder to heat. The exposure of the house to the sun is an important factor when considering these.

Types of extension

The other way to consider what type of extension you want to add to your property is to look at the finished product style.

Single or double storey extension

These are among the most common styles of extension that create a space that can be used for anything. You can extend to the same number of levels as your home, although planning permission is more complicated for two or more storeys than for a single one. This allows you to create new rooms or to extend rooms already within the house.

Conservatories

The other classic of the extension world, these are made with glass walls and roofs to maximise the natural light into the room. Modern developments in glazing have made them easier to control temperature and they are great for projects such as adding a dining room, a home office or an extra living room. The amount of glass means they aren’t always ideal for bedrooms, depending on if you are overlooked.

Orangery and garden room

These are crossovers between the brick built single storey extension and the conservatory. They have more brickwork than a conservatory and often a solid roof rather than a glazed one. But they have more glazing in the walls than a brickwork extension normally would.

Working with what you have

While adding to the property is a good option, you can also look at what you have to see if you can make more of that.

The garage is often a good candidate for this. According to Homebuilding & Renovating, a well thought out garage conversion can increase the value of your home by as much as 10% so this is worth considering when you look at it. Their article goes into good detail about how to plan and design a garage conversion to make sure it is going to be cost-effective from the long-term viewpoint.

The other big conversion option is the loft. We all have one and most of them can be converted in some way into a useable space. There are regulations that apply to the project regarding things like windows and access to the space depending on what you plan to do with it. For example, an organised storage space has fewer regulations attached than a bedroom.

Planning permission and building regulations

The UK now has a system in place called Permitted Development Rights that allow you to do a lot of work to your home without the need for planning permission. There are still rules that apply to the project, so you just can’t do whatever you want but for most types of extension and conversion projects, there’s no need for planning permission.

• That it is no more than four metres in height and isn’t higher than the highest point of the existing building
• Two-storey extensions need to be no closer than 7 metres to the rear boundary of the property
• Side extensions must be just one storey, no more than 4 metres in height and no more than half the width of the original building
• Extensions cannot cover more than half of the garden

There are also rules that apply to your property if it is listed, in a conservation area or national park or a World Heritage site. It is always best to check with your local authority’s planning department about a project as if you do break any of the rules, you can get a fine and have to take the extension down entirely.

Building regulations

Regardless of whether you need planning permission or not, building regulations always apply to a project. This means it will need Building Regulation Approval based on rules laid out by the government to keep a minimum design and construction standard. This looks at issues such as fire and safety, insulation, access and even the drainage system of the extension.

You can send a Full Plan Submission to your local authority where you pay a fee and the building inspector visits at intervals to check the work. or you can submit a Building Notice where you confirm your project complies with the regulations and gives 48 hours’ notice that the work is starting. Surveyors will then visit at stages and let you know any problems. The second is a little riskier as you don’t have approval for the work so always be cautious with this option, especially if you are undertaking a self build extension.

Designing the extension

There are lots of ways to design the extension – you can do it yourself, you can work from a kit or ready-made plan or you can hire an architect to design it for you. It depends on the complexity of the project or the specific requirements you have as to what option is best but if you are at all uncertain, it is always best to deal with an expert.

• Royal Institution of Chartered Surveyors (RICS)
• Chartered Institute of Architectural Technologists (CIAT)
• Association of Building Engineers (ABE)
• Chartered Institute of Building (IOB)
• Institution of Structural Engineers (ISE)

These people will have the academic and technical qualifications to help with your project. Also, make sure anyone working on the project has the correct professional indemnity insurance in place.

Managing the project

Like designing, there are different options for managing the project. If you are self-building, then you will likely to it all yourself. Or you may need contractors for specific tasks within the project. If you use a design and build company, then they can often manage the project for you, arranging relevant tradesmen to be in place when they are needed.

You can also use a builder to carry out the work once you have a plan in place. Do a little research before hiring someone as while the industry is much improved, the old idea of the ‘dodgy’ builder can still exist. Often the problem is a lack of experience for the task at hand so ask for examples of previous work in the area you are getting quotes for.

Other considerations

Remember that during the project, there is likely to be a lot of disruption to the home. Noise, mess and workmen are all part of the extension process so make sure you have prepared for this. You might even want to send the family away for a few days at the height of the project – a great time for a family visit!

There are lots of extension options and many of the choices revolve around what you want from the extra space. By having a clear idea about this, you can find the perfect option, get the regulations in place and have your new space in the shortest possible time.