Do you need an architect or builder to design your extension? Jon from Hylands Homes helps you choose the best route for your project.

When I ask people who they think can design an extension and who they think should do it, more often than not, the reply is an architect. While it’s true they are highly trained and able to design, plan and manage the construction of a new extension, there are a number of alternatives to choose from which I will take you through so that you can decide what you feel comfortable with.

Trained architects are professionals, and professionals are never the inexpensive option. While an architect is the obvious choice, in some cases, employing their services may be a costly overkill.

Your design options

One of the key considerations when embarking on the home improvement journey is the complexity of the scheme. Some of you may want an extension that resembles something off of Grand Designs but the vast majority of people just want something that works, improves their lifestyle and looks great.

Building an extension using standard construction techniques is not rocket science. Most of the parts are off the shelf and any made to measure items such as the windows and doors are made in a factory specialising in their manufacture. So, do we really need to go to the expense of a fully-qualified architect to draw up something so straightforward? I would suggest not. Here are some of the key design options available to you:

Do I need an architect?


The term architect is legally protected. To be allowed to use the title, you must have completed seven years of training and will have to be accepted by the Architect’s Registration Board. You must also hold professional indemnity insurance. While anyone can design a house, unless all of these boxes have been ticked, they can’t legally call themselves an architect. It’s this training and professional status that pushes up the price of an architect. It’s also why the very best can charge eye-watering fees for some of the most complex projects.

If you’re looking for a cutting-edge contemporary extension that pushes the boundaries of eco-design and exploits the latest materials and thinking, then you should probably go straight to an architect. You still need to shop around though, because not all will specialise in the kind of extension you want. An expert in concrete car parks isn’t going to be the best bet if you want a floating cantilevered glass cube, for instance.

An architect is also likely to be the right person to go to if you’re looking to develop a difficult site, such as a plot with a severe slope or tricky access because they will have the skills to mitigate these issues within their design.

The perennial downside of using an architect, and a concern I’ve heard repeatedly over the years, is that while they produce stunning designs, quite often the budget is forgotten and the project ends up becoming unaffordable. This issue can be compounded by architects working to a percentage of the build costs, which acts as an incentive to design a bigger and better house than the original brief calls for.

So, what are the other alternatives?


These professionals apply the science of architecture, specialising in the technological aspects of buildings, including design and construction methods. They work alongside architects and therefore have an understanding of space, materials and aesthetics. Add these aspects together and they’re well qualified to design individual homes.

As they’re not full-blown architects, they tend to charge less and offer tremendous value-for-money. This can be especially true when it comes to contemporary, energy-efficient buildings, as many architectural technologists are qualified to design to Passivhaus standards.

Architectural technicians possess similar qualifications to technologists — although they are not authorised to work as a sole practitioner. Check out the Charted Institute of Architectural Technologists’ website to find members working in your area.


If you were looking to build an entire house then a package company may have been an option you were thinking about. The many package house suppliers in the market rely on great design to sell their products. The basic idea is they come up with a scheme at little or no cost, using their in-house architects and designers. You then fall in love with the idea and commission them to take the project through planning, Building Regulations and some or all of the construction works.

The catch is that they own the design, so if you want to use it you will be obliged to sign up to their timber frame or materials package and that’s where they make their money. The plans, therefore, become the sprat to catch the mackerel, so it’s important for these companies to have exceptional architects and designers on board.

Using a package company is a popular and sensible route into self-build homes, especially for first-timers, as you’ll have access to their support all the way through the project.

Do I need an architect?


Anyone who is not formally qualified falls into this generic category. In effect, anybody can call himself or herself a designer so it becomes all the more important to do your homework. The key things to look for are examples of previous work, which must be followed up with client references to prove competency. You should also ensure you see proof of professional indemnity insurance.

These designers have a role to play. Many concentrate on small-scale projects such as simple extensions and cosmetic remodelling, where the costs associated with a fully qualified architect are sometimes not justified. Into this category would fall the design and build companies who offer stock plans and the resources to build them. Costs are relatively easy to control but don’t expect state-of-the-art architecture.


Lastly, you could have a go yourself. Core versions of 3D design software packages such as Sketchup are free to download and, with the help of web tutorials, give everyone the chance to draw up their own scheme. 

Getting a self-drawn design through the planning process is not at all uncommon, but the key question is whether the scheme has considered if it can be built economically to meet the Building Regulations. 

It’s at this stage where DIY designs can come unstuck where a space has been designed but no thought given to the structural support or the aesthetics of the rooms. It’s what you don’t know that you don’t know, that gets you into trouble and can potentially end up costing you more in construction costs than paying for someone to design it economically in the first place. Many architects and designers will be familiar with the clients who call up having obtained planning permission for their drawings but no idea of how to build it.

If you think this is a step too far for you, another approach would be to use the software to mock up ideas that can be used to inform your brief to an architect or house designer. The more information you can supply will help ensure you are both on the same page from the outset.

Do I need an architect?

How much should you pay?

As professionals, architects expect to be paid handsomely for their work. The very best can charge a fortune, and rightly so some architect-designed homes are more works of art than houses. However, most of us just want a nice home extension that isn’t going to break the bank.

After the financial crash, architects had to revisit their pricing because work was scarce; falling back on the old RIBA scale system, which was a licence to print money, made them too expensive. There are stories of people paying architects tens of thousands of pounds under RIBA contracts and the project not even underway on site.

To get work, many architects reverted to a fixed fee approach and this is the model that I would encourage you to use if possible, whoever you engage to create your scheme. A straightforward design for a bespoke four bed detached home up to Building Regulations drawings can be achieved for around £5,000 depending on complexity. Plans for a simple extension to an existing property, matching the current house style, can be produced for as little as £1,500 if you use a local designer.


Ultimately, it’s your call. For complex, cutting-edge designs, highly energy-efficient homes or where you want to extract the maximum from a difficult plot, hiring an architect will be money well spent. But if you are building a generic four-sided box extension with a flat roof, it may be a waste of your budget, as there are designers who can do just as good a job for a fraction of the cost at that level.

The trick, as always, is to shop around to find somebody who is on the same wavelength as you, who has a portfolio of work that inspires you and who understands your budgetary constraints. Letters after someone’s name mean nothing without ticking those three boxes!


  1. Always take and follow up references so you know what kind of service you will be getting.
  2. Make a record of each meeting and phone call and write notes into an email so both parties have a clear understanding of what has been agreed.
  3. Ensure everyone is on the same page about the budget. If you have £200,000 to spend on your build including all fees but your designer thinks their costs will be added on top, for instance, you’ll soon get into hot water.
  4. Avoid engaging your designer on a sliding fee basis, because this can become a license to print money. A fixed fee gives you greater control over costs.
  5. Make sure any contract has a suitable termination clause in place so either party can escape if it goes wrong.

How Do We Do Things At Hylands Homes?

Well, we kind of take our own advice with respect to deciding what the level of complexity is for each project. If an extension is pretty basic and comes under Permitted Development we may well produce some drawings ourselves to submit to the Council on your behalf. For more complex projects that require full planning consent then we would look to employ our preferred architect to carry out the design, mainly because their knowledge of the local planning policy will enable them to design something that stands a better chance of being approved the first time.

If you would like to speak with us about your project plans then get in contact and we can advise you of the best route. Alternatively, have a look at our process to see what the stages are for a full planning application.