Obtaining a building warrant is the second stage and focuses on the following areas
- Size and actual location of the construction
- Production of detailed drawings by an architect outling materials to be used, thermal characteristics
- Stability, this may require the services of a structural engineer
- If a building is to be taken down a demolition warrant must first be obtained.
I employed a friend of a friend to produce my drawings. He visited the house once and along with my written requirements and the detailed colour drawings i had created on my computer he was able to produce a suitable set of CAD drawings. The price of a set of drawings will vary alot depending upon complexity, size etc but will probably end up being around £500 - £1000.
If you are just adding a conservatory then the plans will be far simpler than the ones we had to produce (which included the extension). Typical areas a building department will be interested in are whether the conservatory has dwarf walls or glass to the ground as this decides on the use of strengthened glass, wall insulation requirements etc. Another area will be whether the conservatory is heated or not, this affects the type of door that must be between the main building and conservatory, an unheated conservatory will require the door to have a higher U-rating (to reduce heat loss).
I completed and sent the following items to the council building control department
- A plan showing the location of the existing property, boundaries and proposed development.
- A full set of architect drawings
- A Building warrant applicatiion form (asks questions like type and purpose of the construction, cost of operation)
- A cheque for the £364.
The warrant application cost (in my case £364) is calculated on a sliding scale based on the cost of operations. e.g. if you think the cost of your project will be between £5000 - £5,500 then the fee expected would be £130, if it will be between
£10,000 - £11,000 then the fee would be £252 and so on, the greater the cost of operation the larger the fee. Note: these prices are only for rough guidance and will vary based on the council and the time that pasted since this guide was written.
If the council disagree with your estimate then they will ask you to change it and resubmit, so don't try and be too unrealistically low with your estimate...
The rest of this guide will go onto to explain only the contruction of the conservatory and not the extension...