Constructing an extension involves a lot of plans and time before any brick is put into place. It might even be considered second only to purchasing a home because it is one of the most important investments any person might undertake.

This is not meant to discourage you because extending your home is an ideal way to add more value to it.
When you find an architect, you will understand that there are a lot of processes to complete and that all of them come with a cost. This is very essential to recall because many companies attract clients with low prices and end up adding costs as the extension process continues. It is important to have a definite architect extension plan cost established ahead of time to avoid this.

This article compiles all that you need to know about architect extension plans cost. You should continue reading to help in accomplishing your plans.

The Cost of Constructing an Extension

The cost of an extension usually depends on where you are. Some other factors determine the architect extension plans costs. These are the materials, size, and conditions of the building project. You must make sure that you take this into consideration before finalizing any architect’s extension plans just to make sure your budget is sufficient.

An Architect’s Fees for an Extension

The services being offered by the architect determine in large part the money they are going to receive from their clients. If the service is just an architectural drawing or just making plans for the extension project, the cost will be low. But if you need an architect to create plans, supervise the planning applications, and still be the manager for the whole project, then the payments will rise gradually.

Calculating an Architect’s Fees

An architect’s payment is usually calculated in one of three ways.

Time – There are those architects who might prefer being paid on an hourly basis, but they are rare. On the other hand, some charge for every hour added either for consultancy or any additions to the project.

Percentage – If the construction project is complex or a large-scale building, for instance, the architect may charge a percentage that ranges between five and twelve percent of the cost of the project. In short, the fees will be determined by the complexity or scale of the project.

Lump sum – Sometimes, the extension plans might be easy and direct. In this case, the architect’s fee is calculated as a lump sum. But still, the total extension cost is always determined by all the tasks the architect is completing for the client.

More Costs to Take into Consideration

Before finalizing the budget for an architect extension plans cost, it is essential to keep in mind the extra costs that must be added to obtain the final sum.

Planning applications – There is a cost for all the planning applications. Sometimes, the architect might include it in the fees for managing the whole project, and sometimes, the client pays it directly to the local authority.

Inspection – Before any extension or construction is carried out, the architect is supposed to submit a building notice to the appropriate authority. An inspector will certify that the project meets certain standards. After this is done, you will pay an inspection charge.


If you were wondering how to determine an architect extension plans cost, the above article will be of great use to you. Now you know how to establish the cost of an extension, how the architect charges for all tasks, and more.