Preparing For Your House Extension Project

Compiling a Brief

The following questions will help you clarify items related to your house extension project and assist you in determining your priorities. You don’t have to answer all the questions, but the more you answer the better prepared you are to give instructions on what you want. If there are any questions you haven’t thought about previously, just give yourself some time to think it over.

  • What use do you have in mind for the extension?
  • Do you have any idea what size you want the extension to be?
  • What is the orientation of your garden?
  • Is there anything you definitely want to include in your extension?
  • What budget do you want to work to?

Please answer the appropriate questions, more than one in each category if appropriate.

Planning permission

  • I would prefer to avoid having to make an application for planning permission and avail of planning exemptions if possible.
  • I don’t mind having to make a planning application should the size or location require it and in order to get the best solution?

Integration of the new living space.

  • I am concerned how the new space will integrate with the existing space in my home.
  • I may need to re-configure the rooms in the existing house to get the space we need.
  • I want the new living space to act as a separate space.
  • I want the new living space to be integrated as part of an existing room (e.g. extension to kitchen).

Natural light

  • I am concerned about the loss of natural light to the existing rooms in my house.
  • If possible I would prefer not to block the windows to the rooms of the house.
  • I want the new living space to be flooded with natural light.
  • I want a reasonable balance of light in the new living space.
    • If possible I would like to avail of natural light during:
  • The first half of the day
  • The last half of the day
  • Both


  • I want the new living space to be very well insulated.
  • I would be willing to pay a little extra to get higher thermal performance (insulation values.

Natural light and thermal performance work in balance. The more glazing in the building, the poorer the insulation value of the building. Which of the two is more important?

  • Natural light
  • Heat insulation

Style of building

  • I have a particular roof style in mind.
  • I want a style that will be the same as my existing home.
  • I want a style that is different but complimentary to my existing home
  • I would prefer a more traditional style of extension.
  • I am willing to consider a more adventurous design solution.
  • Are you planning to continue living in the house for the foreseeable future?

Construction Methods.

  • I would like to know more about the different construction methods, such as solid concrete blocks, cavity blocks, steel frame and timber frame.
  • On the above, in particular I would like to know about permanence, longevity, insulation performance, sustainability and environmental impact.
  • Advances in building technology allow buildings to perform better (better weathering, air-tightness and insulation) and are more sustainable. Is this important to you?

Items to confirm when talking to various companies.

  • Are the building works guaranteed?
  • Does the company have adequate liability insurance?
  • Has the company the financial footing to ensure completion of your house extension?
  • Does the company have a good track record and have they been in business long?
  • Are the building works certified by a separate professional office as compliant with current Building Regulations?
  • Are you applying for planning permission or will you receive a certificate to confirm the work is exempt through the company undertaking the work?
  • Will drawings be produced to give an accurate view and specifications of the project?
  • Does the company have experience in designing solutions that will meet your needs in the best possible way.
  • Does the company have a particular expertise in the area?

Well done! Even thinking about the questions above will help to consolidate your thoughts and give you more clarity on what you want. Another very useful exercise is to start gathering images/clippings of styles and finishes you like.