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24 Things You Need to Know Before You Renovate

building site
(Image credit: getty images)

Taking on a renovation project is both a challenging and rewarding experience. But unlike self build, with a renovation you are never starting with a blank page.

The process is complex and can be prone to unforeseen issues and expenses, so being well prepared is key to a successful project. Before you take on your own project, follow these tips from those who have been there and done it.

1. Make Sure You Get a Building Report

You should always commission a building report from a chartered building surveyor before buying. However, do bear in mind that a surveyor will not be able to uncover hidden problems and will not usually give an idea of the costs.

2. Be Prepared for Competition

When there is a lot of interest in a property it will often go to sealed bids. The estate agent will let you know the date and time in which all bids have to be in by. When submitting your bid you will need to provide a letter stating your final offer, along with your solicitor’s details and ideally a mortgage offer in principle from your lender.

Often it pays to write the letter to the owner of the house, setting out why you are a good choice — no chain, big deposit, etc. Include a little personal information too on why you want to buy the property and are a reliable choice.

3. Save on Surveys

If you require a mortgage, your lender will insist on a valuation. If you also want a full structural survey, ask your lender whether your chosen surveyor is on their panel for valuation reports and, if not, if they could recommend one locally who is — it saves paying for two different surveys, saving £100s.

4. Have a Strict Schedule

Without a schedule the whole process can become chaotic, with tradespeople overlapping, and many jobs that could have been carried out at the same time to save on costs being undertaken separately.

A schedule lists what work needs to be done to the house, and in what order. In addition to having one schedule for the entire project, it is often helpful to break a project down into phases, such as ‘kitchen extension’, ‘moving bathroom upstairs’, ‘loft conversion’ and so on, and have a schedule for each.

5. Budget for New Electrics

Electrics in old buildings will often require updating — look out for old-fashioned fuse boxes, light switches, round pin plugs and fabric-coated flex. To rewire a typical three bedroom terrace measuring around 100m² will cost between £2,500-£3,000. This should include removing the old wiring, installing a new consumer unit and lifting and replacing the floorboards — it will not include replastering.

6. Look for Radiators

A lack of radiators should alert you to the fact that there is no central heating system in place. Adding a modern heating system to a typical house will cost around £2,500-£5,000 — don’t forget to add it to your budget.

7. Be Subsidence Savvy

Subsidence does not always spell disaster. Indications of subsidence include big cracks that seem to have grown from smaller ones, particularly when they get wider and appear in the corners of window and door openings. Cracks that are more than 3mm wide on the exterior of a building should also raise the alarm. Look too for doors and windows that have begun to stick.

The main issue with subsidence is that it will be hard to obtain buildings insurance — you will be left to either pay for any relevant treatment yourself, then get insurance, which in turn is likely to have a big premium, or to get the seller to make a claim against their insurers, allowing work to be carried out under their policy. All that may be needed is for trees to be removed or drains fixed. However if the building has already started to fail, underpinning may be required, which could cost £10,000s.

8. Beware Damp

There are several causes of damp, with some more costly to fix than others. Damp is often obvious — water marks on floors and walls being tell-tale signs. Occasionally condensation will also be visible on walls and windows. Causes range from leaking gutters and blocked drains (which are fairly simple to put right) to inappropriate modern interventions, such as cement renders, concrete floors and injected damp-proof courses. These are a little more costly to remedy.

9. Check for Rot

Make sure you’re on the look out for rot — a fungus that can destroy timber. Rot appears in badly ventilated conditions and it is often found in the roof space or under floorboards in old houses. Look out for cotton wool-type masses and a strong musty smell when you lift the carpet.

Getting rid of it will cost around £1,000. Wet rot is not so much of a problem, occurring in timber exposed to high levels of moisture.

10. Don’t Let Cracks Scare you Off

Don’t let cracks scare you off. People immediately assume all cracks are bad, but they are not always a sign of subsidence. Cracks evident in just a single brick or in plaster by a window or doorway are not usually signs of a structural issue. However, more extensive cracks that seem to follow a pattern, such as through several bricks, can point to something more worrying.

11. Is it Habitable?

If the property is unlivable, be aware that some mortgage lenders will refuse to lend on properties that are uninhabitable, while others will lend based on the current value of the house but then will not lend anything further until the project is complete — known as applying a ‘retention’ to the borrowing.

(MORE: Everything you need to know about renovating a house)

12. Don’t Rip Out Ground Floor Bathrooms

Downstairs bathrooms are very common in old houses. To create a new bathroom on the first floor to replace an existing bedroom should cost around £1,500-£2,500 — but this will mean you lose a bedroom somewhere.

On the plus side, if you are replacing or fitting a bathroom upstairs, a downstairs bathroom allows you to keep the facilities in use while the new one is fitted, plus plumbing and waste will be in place should you fancy a downstairs shower room or similar.

13. Check the Roof

Broken or missing roof tiles, flashings or underfelt and worn pointing on the roof need to be noted. If just a few tiles need replacing, it will only cost a couple of hundred pounds, but if the damage is extensive, a new roof may be required — a job which will cost about £2,000–£3,000 for a typical three-bed house.

14. Get a Measured Survey

If you’re planning on carrying out significant design work on the new property, make sure you get a measured survey (i.e. laser measures and scans of the property). It ensures the design is accurate and eradicates any element of guesswork.

15. Prepare for Auctions

Buying at auction can be a daunting process. It requires quick decision-making and the acceptance that when the hammer falls, if you are the successful bidder, then there is no turning back. It pays to sit in on a few auctions first to get a feel for the process, and to thoroughly research the property before the auction, carrying out all the relevant property and land searches to avoid nasty surprises later.

Plus a survey — all within the four to six weeks you’ll get between the auction being announced and the bidding day. So, you must be prepared and able to commit a significant amount of money without being sure the property is yours, along with a 10% deposit for the day when the contracts will be signed, and the remaining 90% within 28 days. You’ll need to commission the regular conveyancing work to check boundaries, titles, and raise questions with the vendor’s solicitor, too.

(MORE: On a budget? Here are 10 tips to help stick to your renovation budget)

16. Plan for Living

If the property you buy is uninhabitable, you will need somewhere to live while you make it liveable. If you want to stay in your old home while the work is carried out, some mortgage providers offer an option whereby you have your own home valued upfront, and then the sales figures for your property are taken into account for your borrowing needs. 

Once you complete your renovation, or often just before, you’ll then put your old house on the market. Once it sells, the final figures are worked out.

17. Renovating is Difficult

Depending on the scale of the work you’re carrying out, you should prepare yourself for a few practical issues along the way. Namely, an inevitable period of time when you’re without basic services as a result of moving boilers, electrical meters, consumer units and so on (also, a common cause for delay at the start is dealing with utility companies, so plan ahead). 

Dust is the other thing that many people get fed up with — minimise it by sealing off areas of work in phases and leaving the momentous knock-through until as late as possible (i.e. keeping the work outside as much as you can).

18. Know Your VAT

Most suppliers will have to add 20% VAT to all quotes for anyone carrying out work to an existing home. However, if the house has been empty for more than two years you should be charged the reduced rate of 5%. Check out HMRC VAT Notice 708 for details.

19. Take Out Adequate Insurance

Once you exchange contracts you become responsible for the site and you must therefore have adequate insurance. If you are taking out a mortgage to fund the project, your lender will not release any money without insurance being in place to cover calamity such as flooding, theft or fire to the property. Renovation insurance should include public and employers’ liability, cover for building materials and works, the existing structure, accident cover and legal expenses.

Get a quote now to protect your renovation

20. Keep the Windows

If your reno project has the original windows still in place – likely to be timber or metal – then do all you can to rescue them before you even consider replacing. Even if there is extensive damage, they can always be repaired. Conservationists advise that, providing there is at least 50% of the original remaining, a window should be repaired rather than replaced.

21. Use Structural Engineers

If your project involves the removal of load-bearing walls, cutting into roof timbers, widening window or door openings or removing a chimney breast, then consulting a structural engineer is a very good idea and often essential. They will be able to advise you on the placement, size and type of steel beam required for the removal of walls, etc. Budget £500–£1,000 for a simple project.

(MORE: Common renovation mistakes and how to avoid them)

22. Consider a Warranty

Warranties are not essential, but are a good idea. They will cover your house against flaws in the design, materials or build quality, along with any problems that occur as a result. Warranties usually run for 10 years and if you plan on arranging one, do it early on as the premiums escalate the further you get through the project.

23. Beware Unknown Costs

You may need to pay some fees to get the house working again, such as reconnecting the water supply, cleaning out the septic tank, etc. 

Other fees which may surprise you include valuation fees (usually based on the value of the completed property) and, with some of the renovation mortgages, there may be a fee to pay before the release of each stage payment. 

Simply put, taking on an old property means dealing with the unknown. Which means unknown expenses, too.

24. You Don’t Always Need Planning Permission

You might not need planning. A significant number of renovation and extension projects won’t need planning approval at all. These include internal improvements that don’t affect the external look of the building and small extensions. These will be classed as Permitted Development, and you can find out exactly what type of project you can carry out at

The Government recently completed a consultation on changing Permitted Development rights for some types of project, including single storey extensions, but as yet has not decided an outcome. Other larger-scale extensions will require planning approval in the usual way.