Extensions are really a “cross” between a renovation and a new build. – They include some of the characteristics of both types of project. You often need to apply for Planning Permission before you start, but they also involve having to “take out the old stuff” and “put in new”.

For that reason, I thought it worthwhile giving them their own section; discussing the design and planning stages.

Before you start anything else, check on the situation regarding “whether or not” you will need Planning Permission with your local Planning Office.

There are Planning rules regarding extensions. You could well find that you don’t need to make a Planning Application, but until you check, you won’t know. – What you don’t want to do is to spend a few weeks going through the process of designing and possibly spending money, - only to find out that you won’t be able to build because of some “local” Planning restriction or other.

There are fairly simple rules which dictate whether you do or not you will need planning, but these can vary from area to area. – Have a look at the section “Do we need Planning Permission” for more information, and also on the web site:

 

Renovation: When you start out on a renovation project, your task is to “improve an existing property” to the extent to which you need to, in order for you to live comfortably in it.

You also (usually) hope that you will increase the value of the property by more than you spend on it (in fact, that often doesn’t happen. – a lot of renovation projects don’t “break even”, they “recoup” their cost over a number of years. – So, if you are thinking of doing a renovation project for profit, be very careful before you commit yourself – get everything “costed out” as accurately as possible first).

New Build: When you start out on a New Build, you plan to “create a completely new entity” which will supply you with the “space”, the “quality” and the “creature comforts” that you want and need. – Hopefully doing so at a cost which is significantly less than its “market value”.

With an Extension, you are doing a bit of both! - You are improving an existing property to make it comfortable for you and your family to live in, and the way you do that, is by building a new structure, “attached” to it, which you generally hope will increase the value of the completed property by more than it cost, so that it at least makes your input worthwhile.

 Unless the extension is so large and complex that it is “getting on” for being equivalent to the size of a new house, you probably won’t need the services of a full, high profile “Architect’s Practice”. - But, if there is a small “Architect” “Architectural Draughtsman”, or a “Draughtsman” somewhere near to you, it’s worth approaching them to get a price for surveying your existing property, designing the extension and helping you to apply for any Planning permission and Building regulation approvals that you will need. – If you are not already “up to speed” with the “planning” situation, they will also usually be able to advise you with that.

Often with and extension, what you are doing is: “From an existing building and an existing layout, trying to create something new, - that you would be happy with, if you were starting from scratch and building a new property”.

Getting your “ideal layout”, out of an “existing property”, which at best can only be “modified”, and then “added to” is not often a fully achievable goal.

However, what an extension CAN give you is the ability to remain in the house where you may have lived for many years, and be settled in (You may be happy with schools, neighbours, the location etc). - If that’s the case, then the fact that you don’t quite get the “flexibility of design” that you do with a “new build” can be of secondary importance.

Because of that fact that in many cases you will already be living in the property, you will often know exactly what the problems are with it, and the chances are that you will actually know exactly what needs to be done, and what the floor plan will be before you (or anyone else) has put pen to paper to start designing it!

You may have had many discussions within the family along the lines of: “We could do with an extra room downstairs and it’s about time the kids had a bedroom each. – If we built an extension, we could knock through from the kitchen, make a dining area and a larger kitchen, and we could turn left at the top of the stairs and have 2 extra rooms there, - one extra bedroom and an office”.  If we did that we wouldn’t need to think about moving, and we could just do a remortage on the house to pay for it”.

That’s often the way it works. - So, by the time you actually go and see the designer, you will have sketched exactly what you want (see previous two sections), shown him a few photos, and got to the point where he can pretty much get on with designing your new “building”.

As part of the process, your designer will need to sit down with you and discuss both the extension itself, and any other works within your existing property which will form part of the project. – New kitchens, bathrooms, decorating, carpets, tiling etc.

The other thing they will want to do is to come and survey your existing house. - They need to do this to pick up many of the details which will need to be included in your drawings.

1) The dimensions of your existing house, height of the top of the roof, etc.

2) The condition of the existing property.

3) Positions and sizes of windows, doors and anything else that features along the wall that you are thinking of attaching your new extension to. The designer will assess whether they can use any of your existing openings as part of the new design. (For example, will the position of your back door suit the layout? – It may be ideally positioned to give you an internal door into your extension. - If so, then the time and cost of supporting the external wall, inserting a lintel, and forming a new opening can be saved).

4) Position of drains, manholes, electricity and gas boxes, and the route and “access point” (stop tap) of the water main.

5) Existing services in the house, especially on the wall where the extension will be built, - together with the general condition of the electrical and plumbing installation in your house as it is at present.

6) Heights of your existing ceilings, thicknesses of floors, level of ground floor slab, widths of external walls etc

7) They will need to note any external features which may impact on the new structure, such as levels of the ground, trees, boundary lines, fences or garden walls.

8) They will also have to bear in mind the impact that your extension will have on 1) Neighbouring properties 2) General access.

After carrying out this survey (which could cost you anything from a couple of hundred pounds “upwards”), and being able to look at your sketches, and listen to your ideas, wishes and requirements, - your designer should then be able to sit down with you and give you an outline of how he / she sees the whole project going. - In respect of the “practicality” of the building process itself, “Planning Permission”, “upheaval”, and “timescales”.

He / she should also at that stage (if they are experienced in this sort of work), be in a good position to be able to give you as “ball park” figure of a price for the project.

This will be dependent upon a number of things, including your “level of specification”.

An extension may cost £20,000 for the main structural work, but you can then easily spend anything between an extra £5,000 and £25,000 on you new kitchens and bathrooms, - which can more than double the overall cost. (If you read the kitchen and bathroom design pages in this guide they will give you some guidance which could help to keep the cost of these sections down).

Once the full drawings are completed (which with computer aided design, should not take long, or cost too much), you are then ready for the next phase, - either “Planning Permission” or “Estimates / Quotations”. (We will assume in this case that you don’t need Planning Permission.- If you do, then you will need to go through that process before moving on to the next phase. – See other section of the guide for advice on Planning / Building Regs).

You will now need to get tender documents prepared so that you can “go out” for prices for the work.

To do this properly you should think about using the services of a: “Quantity Surveyor”, “Estimator” or possibly a “Project Manager” you should be able to find locally to you in the directory. Possibly your designer may be able to offer this service, or, if you are confident enough and have the time, you could always have a go at doing them yourselves (if you compile them yourselves and make a mistake or miss something it could cost you a lot of money “further down the line”).

Part of your plan for the project may be to try to do some of the work yourselves. However, because of the “nature” of an extension and the often complicated process of creating a new building and attaching it an old one, you are actually more likely to have all the work done by either a main contractor, or various subcontractors.

If you try doing some of the “minor” parts of the work yourself at the same time that you have subcontractors doing the main building work, you could find that you actually slow down the progress (they may be waiting for you to dig a hole / knock a hole in a wall / build a bit of scaffold / clear out a room etc) before they can do a certain part of the work. - This can end up causing friction between you and the builders who want to get finished and onto the next job, and it can also end up with you getting “billed” for their “standing time”.

So, if you decide not to do any of the work yourselves, your choices are now to take on a “specialist” main contractor, or if you want to try to save some money, hire individual “sub contractors”, to carry out the individual sections of the work.

My advice here would be to make sure that there is a “coordinator” of some sort on site (e.g. a “Foreman”), who will oversee EVERY part of the project. - There are dozens of “bits” which go together to make up a project like this, which all need to “programmed” and often need to be done in a “strict order”.

If these things aren’t done when they should be, the whole project can swiftly fall apart and turn into a complete mess, - which will take far longer than it should to complete and cost more than it should.

If you have “Building Management” skills and a reasonable knowledge of the subject, you might be tempted to manage the job yourself. However, if you are “new to the game”, I would strongly recommend considering taking on either a “Main Contractor”, who will look after everything, or that you find a Foreman / Project Manager to look after the day to day running of the job and to make sure everyone is doing “what they should” “when they should”! (see Trade Directory for “Project Managers”).

Always get at least three quotes. – Someone once quoted me the theory that: “The cost of a project reduces in direct relation to the number of quotes you get for the work”. – I tend to agree (up to a point). - Once you have the tender documents prepared, it is not much more work to send six sets of “paperwork” off to different sub contractors, than it is to send three sets. – 6 Sets may just get you in touch with a company who just happen to be finishing a contract and who don’t presently have another lined up, - so they will tend to give you a more competitive quote.

Most people are (rightly) concerned about “Getting the right people to do the work”.

There are many horror stories about jobs being left half finished and contractors asking for far more than the original price, once it is all finished. - Then causing trouble if they don’t get the money they ask for. – This IS a problem in the industry, and it’s one this site is hoping to help reduce.

As I mentioned earlier, if you use the Trade Directory on this site, make use of the “free advice” and “references” tick boxes to find out a bit more about the people you may potentially be giving the work to. – If references are available, check them out. – Don’t feel embarrassed about doing so. – You are going to be investing a lot of trust and money into these people. You have a right to know whether they have a history of getting jobs done right or not. – If you don’t check references, you are asking for trouble. (If they say they have references and then don’t give you any, -insist! – Before you give them the job. – they may not actually have any, and be hoping that you will forget to chase them).

A good contractor will give up their time free “up front”, and they will make sure that you know all about how they would go about tackling the project.

If at all possible, get “FIXED PRICE QUOTES” in writing, dated and signed by the boss. – You can do this fairly simply by getting them to sign each page of the tender document to indicate that they have read and understood it. You should also add a clause to say that if there is ANY change in the fixed price, for any reason, that before the cost is incurred, details of it should be given in writing, along with the reason for it, and that if this reason is not accepted, then the extra work should not be done. You should also add that you will give “reasonable consent” to such matters.

Also get them to add a sentence saying how long the quote is valid for.

For these sorts of projects, contracts are fairly rare. – Most people are happy to work with a signed and dated “fixed price quote”. – However if yours is a large project, or if you would feel happier getting everyone to commit to a contract, you can probably get your Lawyer to draw something fairly simple up for you.

It is common practice in building for the client to keep 5% retention on payment for the work done. – This is to cover them for any expenses incurred which may be due to the contractor not fulfilling their obligations.

The retention is normally returned after 6 months assuming that there has been no “call” on it. – If you decide to include this as part of your contract with the contractor, make sure they are fully aware of it before they submit their price. If you try to add it later, they may disagree with its inclusion.

If you tell them about it “up front” (which you need to), and they know they are not in competition with anyone, they will often just add 5% to their quote to cover what you intend to hold back. – This makes it all the more important for you to get quotes from at least 3 (and preferably around 6) people for each section of work.

One of the major problems with this type of project is “getting it finished”.

Many contractors will make a good start, but then slowly reduce output and it can sometimes be a real “trial” to get them to finish the work.

The main tool you have in your armoury to guard against this is your money! – If you control the money situation, you usually control the progress on site far better.

Try not to give “deposits” before any work is done. If this is how the projects starts out, it will generally continue in the same manner. – You MAY need to pay upfront to order specialist items, but apart from that, if the contractor is decent and genuine, they should not require paying until they have done some work. – You don’t pay for your shopping before you put it in your basket, why should you pay for bricks you have not got?

Always pay “In arrears” and make sure that your contract covers the stages when payments will be due. Stick to these payment points and keep your payments prompt so that there is no comeback or disruption to the project.

If you keep hold of the purse strings, you keep control of the job. The contractor is more likely to give you priority if he knows that until he finishes that “little plastering job”, he doesn’t get his next payment, and until he finishes the whole thing, you will be keeping a substantial amount of his money. – The trick is to try to set things up so that the contractor “makes his profit” at the end, and that interim payments cover just the ongoing cost of the building works. To try to achieve this, try to “weight” the last payment to be more than the rest. For example, maybe you’ll agree to pay 18% at completion of the ground floor slab, 18% when it is “roofed in”, 18% after “first fix”, 18% after plastering and 28% when it’s finished (also keeping 5% retention on each payment). – If your contractor won’t agree to that, ask why and if he doesn’t have a good reason, choose someone else!

You will need to make sure that your project is fully insured and that you obtain any structural warranties that may be required by your mortgage provider.

Even if you don’t have a mortgage, make sure that you get:

1) Building Regulations approval:

This should be obtained before you start work on site (see sections in this guide on Building Regs). - This will involve either you or your contractor getting the work inspected at intervals and receiving a certificate of completion once it is finished. – If your contractor is responsible for organising the inspections, then make sure that you are satisfied that the work has been approved before you make any payments at each stage.

2) A Structural Warranty:

This will be needed if you sell the property at any time in the future, as proof that the work was done to a satisfactory standard. This will again involve inspections of quality at various stages.

There are companies who can offer both inspections, and this may help to reduce the number of phone calls and meetings that need to be organised to get the work “passed”.

3) A guarantee for the work from the sub contractors of main contractor.

The work should be fully guaranteed against faulty workmanship, and if possibly you should try to get a “6 month snagging” clause included, which will allow you to compile a list of any problems with the work after 6 months.

This work would then need to be completed to your satisfaction, at which stage you would agree to release the “retention money” to the contractor.

All in all an extension project should not present as many upheaval problems as many renovations projects, and far less than most Self Build projects.

An average extension project which does not need Planning Permission could be planned and completed within 6 months.

Generally you will be able to remain in occupation whilst the work is done, and until the new structure is roofed in and weather tight, you may not have ANY interference to you day to day living inside the original part of the building.

Once you DO start to be affected on a day to day basis by the work that is being carried out, you need to make sure that THAT part of the work is completed as quickly as possible. Unfortunately, that is just the time that, if you have not got the contractor “tied” to your contract financially, they can sometimes tend to start to give other “new” projects some of their attention, to the detriment of yours.

However, if you follow the guidelines in this section, plan the project correctly from the outset, get a selection of quotes, have suitable contracts drawn up, and keep control of the finances, there is a good chance that the project will run relatively smoothly and with minimum stress.