Do you need a foundation for a conservatory?

Chartwell green timber conservatory Interior view

Planning your dream conservatory space can conjure up many queries along the way. A common question that crops up is:

Do you need a foundation for a conservatory?

In short, the answer is unequivocally yes. Whether it’s constructed from uPVC, timber or aluminium, foundations are needed as much as any permanent structure or extension requires.

Why do you need a foundation for a conservatory?

All safe and sound buildings require a foundation, to effectively transmit the load of the structure to the ground beneath it. Varying from one installation to another, adequate foundations are generally made from concrete. It’s crucial to understand that the majority of conservatory issues post-construction are due to below-par foundations.

Chartwell green timber conservatory

What kind of foundations do conservatories require?

Conservatories are only as strong as their foundations, so the deeper the better. However, the type of foundations depend on 7 key factors;

  1. Type of soil e.g. loose soil may require piled foundations.
  2. Ground condition
  3. Adjacent structures
  4. Trees
  5. Drains and sewers
  6. Conservatory size
  7. Whether it’s on a landfill site

How can adjacent structures affect conservatory foundations?

Digging conservatory foundations incorrectly has the potential to undermine adjacent structures. Therefore, experienced conservatory installers will know that it’s good practice to excavate at least to the same depth as the bottom of the foundation to the adjacent building.

Edwardian conservatory

Is there any other legislation that applies to conservatory foundations that I should know about?

If your conservatory foundation work affects near or on your shared property boundary, aka ‘the party wall,’ you must notify your neighbour. This legislation is covered by the Party Wall etc. Act 1996.

Visit the Party Wall Act 1996: Explanatory Booklet for full details.

What are the consequences of a conservatory with substandard or no foundations in place?

As many conservatories fall within ‘permitted development rights’ and do not require planning permission, homeowners across Hertfordshire & Middlesex can unfortunately suffer from substandard foundations if due diligence isn’t taken. Substandard foundations can cause:

  • Reduced energy efficiency
  • Subsidence (caving or sinking)
  • Conservatory demolition due to incorrect placement.

A reliable conservatory installation from a company you can trust

As you can see, foundations are exceedingly important for the creation of a safe and sound conservatory that lasts for many years into the future. Get in touch with the Chase Window team for further information or to begin your conservatory adventure very soon.

Related to this post: House extension ideas and advice for semi-detached houses


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Enfield, Middlesex

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