Just like with any large-scale home project, it is always worth sense-checking your plans for your home extension before you actually start working on it. Unless you are in a situation where money is absolutely no object, we would recommend speaking to a trustworthy local estate agent who can then give you an opinion on whether your current plans would add any extra value to your home.

The estate agent will also be able to give you some kind of indication of how much your home's value would increase. This can then, in turn, assist with informing the budgeting of your project.

There are some extension projects that can be performed on your home without the need for planning permission. This is referred to in law as "permitted development rights". Under these rules, a rear wall of a detached property can be extended outwards by eight metres to the rear if it is a single storey and three metres if it is a double storey. This is then reduced to six metres with a semi or terraced home.

There are also important height restrictions to be discussed when looking at planning permissions and permitted development. A single-storey extension cannot be any higher than four metres to the ridge and the eaves. The ridge heights of all extensions must never be higher than the existing property. Double-storey extension must never be closer than seven metres to the property's rear boundary.

There are also other conditions that need to be met. Firstly, for example, if the extension is more than half of the area of land around the original home, then planning permission will be necessary. It is also important to remember that any extensions need to be built with very similar materials to the existing property.If your home resides in a conservation area, then different planning rules can apply. If the home is a listed property, then it will be necessary to obtain listed building consent.

It does not matter whether your project will require planning permission or not; all renovation projects need to comply with building regulations. You will need to make sure that whoever actually carries out the work on the project can either self-certify the work or can discuss with the local Building Control Officers in your council to have all their work certified.

For self-certifying workers, we are discussing Gas Safe registered gas engineers, NICEIC-registered electricians, FENSA-accredited window fitters, and so on. If all of the necessary requirements are not met, then you can be served with a notice that will instruct you that you need to take the extension down. Without the relevant Building Regulations certificates, you will also have a lot of trouble with selling your home when the time comes.

Before your home project begins, it is important that you get in touch with your home and contents insurance provider. You need to let them know all of the plans for your home. The new extension is likely to increase the rebuild costs of your home, and insurers will take this figure into account when they are pricing premiums. While the building work is being undertaken on your property, there is a chance of your home being put at risk.

If you do not tell your insurer about this, and then there actually is an issue with your property at some point, then you might find that your policy is completely void. Your insurer will tell you if your current home policy will cover the new extension. It is common to find that your premiums increase. In some situations, the insurer may be unable to cover the property. In this event, you will need to locate a new provider before your current cover is cancelled.

One more helpful tip here is to ask builders that are working on the project whether they have professional indemnity insurance so the costs can be covered in case something goes wrong.

If you are the owner of the leasehold to your property rather than the freehold, then you will need to take a look at the details of your lease to make sure that you have the right to make alterations to the property. This is usually subject to approval from the freeholder. 

We would recommend getting in touch as soon as possible with your freeholder and telling them about all your plans, as there can often be additional costs involved in order to obtain their approval and sign-off. 

As we are sure you know, building projects can very commonly be a major cause of disputes between neighbours. If planning permission is required for your home extension, then your neighbours will be contacted by the local planning authority.

We would recommend letting your neighbours know about your plans for your home well in advance, especially in cases where the work on your home might lead to disruption.

A party wall is a shared wall that can be found usually between a terrace or a semi-detached house. The party wall divides the homes of two separate owners. This can also include garden walls that are built over boundaries and excavations close to a neighbour's home. This means within three or six metres, depending on the exact depth of the new property foundations.

Party wall agreements between neighbours are very commonly required for property work such as extensions and loft conversions to go ahead. This is because they require the property to be adjusted with the insertion of steel beams, the digging of new foundations, and a damp-proof course.