Two Storey Side Extension, Quotes v Estimate

A question about : Two Storey Side Extension, Quotes v Estimate

We have received 3 prices for a 2 storey side extension. We are in Greater London.

2 are quite close but the 3rd is a fair bit lower. Although we asked for quotes the lower one has been labelled an estimate.

The prices are

Ј80,810
Ј79,956
Ј59,400

There are a couple of differences (the higher ones allow for Ј1500 of bathroom bits and bobs for example) but nothong to account for Ј20,000 !

The extension is very straightforward. 2 storeys up on the side with a hipped cut and pitch roof. Block and beam floor. The new area only interacts with the existing building in three places. 1 is an existing door. 1 will be a new door. The third is the bathroom which will have to be taken across.

We have architects plans, struc engineers report, permission, building regs and are not in a rush.

The new floor space comes to 50 m2.

Which amounts to Ј1600 per m2 and then Ј1200.

Are the first ones too high or the latter too low do you think?

Do you think the contractor working from an estimate would find a way to pile another Ј20,000 on as the build progressed ?

Or are the quotes high because they are quotes and builders don't like to get caught short.

All ex vat of course (depressing!)

Best answers:

• not best to answer but i know i wouldn't be paying Ј16k in VAT!
• Are they like for like quotes, or you just let them quote based on drawings without specs? We have found that sometimes cheaper quotes may not include fittings/plumbing for sanitaryware etc, ie only shell, skim and electrics.
  We are currently extending our house, 2 storey around 35m2 total, with 3 bathrooms, wet underfloor heating and full new unvented CH system for Ј67k ex VAT. Tiling will be extra, and so is the supply of sanitaryware but the fitting/plumbing of all bathroom accessories are included in the quote.
  We've not gone for the cheapest quote, we appointed the builder who supplied the most transparent quote on costs based on what we wanted.
• There are some small differences. The middle quote includes Ј1500 for a bathroom suite. But we had a good talk with all of them to ensure they would quote for the same job.
  So the quotes do not include decorations, floor finishes or tiling. Or taps, supply of boiler, door furniture. They do all include bathroom fitting, plumbing, electrical work.
  Honestly I don't see where the Ј20,000 difference comes from.
  Still a couple of quotes to come in but I think the top two have priced themselves out at the moment. Ј100k (with vat) and then boiler, fittings, floor finish, decoration, furniture to come... that is too much.
  My concern really is that they are all too much and the estimate will creep up in that direction. I would rather not do it at all if we currently can't afford it rather than hiring the cheapest guy on estimate and finding out halfway through that we can't afford it !
  The optimistic side of me wonders whether the quotes are high chiefly because they *are* quotes and that they have been padded to ensure the builders don't risk losing money (or not making any!). Does that happen?
• Bathroom fitting and plumbing are not cheap, how many are you having. If it's only one then your highest quotes sound excessive, especially it excluded provisional sums for boiler, heating and bathroom supplies.
  I don't think builders will price anything with the risk of losing money to start with, they either don't want the job (high price) or missed something in the quote (unknowingly or knowingly). The latter will mean they priced the quote to 'win the job', knowing that things will need to be added/changed as soon as works start. One example in our case is the depth of foundation, our specification said 2m deep foundation, the cheapest builder quoted with only 1m foundation, upon querying he said need to add Ј5k +VAT for additional piling/extra depth. (You're then left wondering what else has he missed out?) Any good builder should be able to provide transparency in their quotes, or explain how the quote was built up (ie labour, plant, materials, what's included in quote, what's included in provisional sums, markups etc)
  Depending on the quality of the cheaper quotes, you may have a preferred builder in mind and if they are the most expensive, maybe you could share the cheaper quotes with them ask them the difference?
• If you ask for quote and get an estimate them without doubt, that is going to come back and bite you later down the line. I would certainly be wary that two quotes are similar but an estimate is 25% cheaper. The estimate allows extras to be added with the scope of works.
  I think Ј1200 is a bit optimistic in London.
  Nobody likes to be caught short, but no one is going to be adding Ј20k of contingency either.
• I would guess the cheaper one is the one that has missed something or will end up costing more by the end of the job!
  The reason to get three quotes is so you can get an average, if you are going with the cheapest I would make sure they have qualified everything in the quote - I know that people on here will tell you 1000 or 1200 is normal for a simple extension but I've not seen one coming back from pricing under 1500 for a couple of years
• Fascinated by this as about to embark on a similar project but 70m2 addition with knock through in dining room downstairs and a bedroom upstairs.
  Our architect has indicated we should be able to get the thing built for Ј1200 m2 (just the basics - plastered etc ready for painting). Have had a couple of builders round to quote (no PP or building reg yet) and their prices correlated with the architect.
  My plan is to get several quotes and speak to previous customers regarding experiences. In my view its worth paying more if you have the following
  1. seen examples of the builders work.
  2. Spoken to previous customers regarding the builder (tidiness, deliver project on time, deliver project on budget).
• I think Ј1200 would be optimistic anywhere, not just South East or London (especially if that already including VAT!). Ј1200/m2 just the shell, by the time electrics, plumbing, windows etc are added, that'd be a lot more.
  Our architect recommended Ј1500/m2 for budgeting purposes (on the shell with electrics and plumbing), and add the other 'bells and whistles' on top eg underfloor heating, boiler, provisonal sums for sanitaryware, contingency etc
  Definitely ask the questions and get builders to clarify/quantify their quote upfront, and see their work, talk to their previous customers. The more you can clarify and agree in the quote, the lesser 'nasty surprises' to expect.