large victorian conservatory

Are you in considering building your very own conservatory? Or maybe you’ve already hired a professional, but you’d just like to know more about the construction process? No matter what stage of the project you’re in, arming yourself with as much knowledge as possible is always a good idea. This will allow you to plan your time and budget effectively, so you’ll be able to achieve the best end result possible for your conservatory build.

In this handy article, we’re going to talk you through each stage of a conservatory build, along with everything else you’ll need to know about planning permissions, building regulations, average cost for labour, and more.

How to Build a Conservatory

How to Build a Conservatory Base

The first step in constructing a conservatory is building a sturdy base. In order to build a safe and long-lasting conservatory, the ground underneath must be prepared, and a foundation must be properly laid.

  1. Measuring the Area

The very first thing you need to do is carefully evaluate and measure out the area in which you want to construct your conservatory. Take the time to plan out and calculate the dimensions of your new conservatory base, ensuring planned construction abides to all necessary rules and requirements. Mark out your measurements accurately ready to dig out and lay foundations.

  1. Excavation & Levelling

You now need to dig out your measured area in the shape of your chosen conservatory structure. The earth below needs to be completely flat and free of all wasteful soil and debris in order to successfully lay foundations so excavate until completely level. 

  1. Laying the Foundation

When it comes to conservatory foundations, you typically have two choices: laying a traditional concrete base or using a pre-fabricated base system.

The pre-fabricated base (also known as a ‘steel base’) is a fairly new option in conservatory construction. The pre-fabricated base section is constructed from galvanised steel to minimise rusting and the walls are built using brick effect tiles which are securely bonded to the steel frames.

The most commonly used and trusted method of conservatory base construction is to lay a concrete foundation. The basic process of this is pretty simple but creates a strong and reliable base for your conservatory structure.

In this article, we will be focusing on the concrete foundation method.

When setting out your concrete base, you must ensure that each corner is correctly squared and even. You will also need to lay a damp-proof course below the concrete layer.


How Deep Do Foundations Need to Be for a Conservatory?


Technically there is no specific minimum depth for conservatory foundations as it will be mainly dependant on both the conditions of the ground and the size of the structure you want to build. However, in a standard conservatory construction job, foundations should be at least 1 metre deep for a small lean-to and no less than 1.5 metres deep for a larger, sturdier structure such as an orangery.

To calculate the precise depth required for your conservatory build, we recommend that you refer to the guidance of your local Building Regulations office or consult the help of a registered installer.

  1. Build to the Damp Course

You must build up the foundations to the damp course in order to create the floor level for your conservatory. It is very important that you layer up carefully to ensure that the base floor is completely level and even. Leave your base to dry completely before moving on to wall construction.

How to Build Conservatory Walls

With your base foundations in place, you can now begin construction your conservatory walls.

  1. Dwarf Wall

The ‘dwarf wall’ is a miniature wall structure that is built around the base. Dwarf walls are typically less than 1m in total height and constructed from bricks.

Begin laying at the base and work up, placing the bricks and waiting the appropriate time period for the cement to dry. If electrical sockets, phone lines etc are required, you may need to consider the installation of these at this stage. Get in contact with a qualified electrician for further installation advice if unsure.

  1. External Sills

When pre-ordering your external sills, make sure that the measurements are accurately customised to match your construction plans. The sills will be positioned on top of the dwarf wall.

  1. Fixing the Frames

The first conservatory frame will need to be positioned and secured to your property. Once in place, you can then begin fitting the rest. Start from the property and work outwards, connecting securely until the frames meet from the two sides.

  1. Door Fitting

Hanging conservatory doors can be a little difficult for DIYers. However, as long as measurements were correctly followed when pre-ordering your doors, they should just simply fit into place without too much trouble to complete the structure.

How to Build a Conservatory Roof

No conservatory is complete without a roof. There are many fantastic options available today, including classic polycarbonate sheets, sleek glass glazing sheets, and roof tiles. In this example, we’re going to focus on how to install glazing sheets.

  1. Roof Ridge

The roof ridge will be positioned on top of the previously fitted frames. If pre-ordered in the correctly measured dimensions, the roof ridge should fit neatly into place without any issue.

  1. Roof Rafters & Glazing Sheets

Roof rafters will need to be added in between the roof ridge structure and the hip bars. With the roof rafters fitted, you can then install your chosen glazing sheets. It is highly important that you always handle, move, and install your glazing sheets with extreme caution as they are fragile and should not be comprised in anyway before, upon or after installation.

  1. Guttering

Guttering is an important element of your conservatories construction to ensure proper drainage and prevent damage to the roof structure. ‘Box’ gutters are installed to create a sealed guttering system between the conservatory and the adjoining property. Make sure the gutters are securely fixed in place to prevent damp spots and leaking.

  1. Decorative Finishing Touches

This stage is optional and is dependent on the type of conservatory you have chosen to build. Traditional style conservatories often incorporate decorative external accessories whilst modern structures tend to stick to a more minimalist design.

How to Fit Lead Flashing on a Conservatory

Flashing is a weather resistant material which is positioned against structural joints to stop water entering the passage between the seams. Whilst there are many types of flashing material available, lead flashing is one of the most popular and arguably the best choice. For a full step-by-step guide, take a look at our blog on how to install apron flashing on a conservatory. For the full step-by-step process of installing apron lead flashing, take a look at our informative article here.

How to Insulate a Conservatory

A common problem that many homeowners face is keeping their conservatory warm in winter. Due to the way they’re built, conservatories can often get a little chilly when cold weather hits. Thankfully, there are many ways to insulate a conservatory to make it a cosy, comfortable space all year round.

If you’re looking for a quick fix, then simply fitting thick blinds and curtains can be enough to reduce heat lost from your conservatory. External coverings such as felt can also act as an extra layer of insulation, as well as absorbing the sound of heavy rainfall and preventing overheating in the summer.

Take a look at our article on how to insulate a conservatory for more detailed information.

Do Conservatories Require Planning Permission?

As conservatories are part of permitted development rights, they will generally not require planning permission. As long as a set of specific conditions are followed, planning permission will not be needed before building a conservatory.


Your conservatory:

  • Doesn’t cover more than 50% of the land around the ‘original house’
  • Isn’t front on to or constructing any public roads
  • Is no higher than the highest part of the roof
  • Has no raised platforms, balconies, or verandas
  • Has a height of less than 4 metres
  • Isn’t wider than half the width of the ‘original house’ if built to the side
  • Doesn’t extend beyond the rear of the ‘original house’ by over 6 metres for a semi-detached and 8 metres for a detached property
  • Doesn’t have an eaves height more than 3 metres if within 2 metres of the boundary


These rules apply to houses only and may not be applicable to:

  • Flats & maisonettes
  • Converted properties or houses created through the permitted development rights for ‘Changes of use’ or ‘New Dwelling Houses’
  • Properties in designated areas where there may be a planning condition, Article 4 Direction, or any other restrictions

What Is Meant by the ‘Original House’?

‘Original house’ means as the house was first built or as it stood on July 1948 (if built before this date).

What Happens if a Conservatory Is Built Without Following These Rules?

Failure to follow planning permission regulations could result in a substantial fine or even demolition of the conservatory structure.

If you’re unsure of anything, we’d always recommend contacting your local planning council. For further information, take a look at the conservatories article from Planning Portal.

Building Regulations for Conservatory Construction

From October 1st 2008, the construction of a conservatory is considered a permitted development. This means you will NOT need to apply for planning permission as long as a specific set of building regulations are strictly followed:

  • Conservatory must not be higher than your roof
  • No more than 50% of the land surrounding the building has any additions/other buildings
  • Angle of conservatory extension roof must match that of your property’s
  • No verandas, balconies or raised platforms
  • Eaves and ridges must not surpass the height of your property
  • Built no more than 4 metres in height for single story extensions
  • Built no more than 3 metres in depth for a rear extension of more than one story (plus ground floor)
  • Built no more than 2 metres of the boundary of 3 metres for eaves
  • Built no more than 3 metres in depth for a single story rear extension and 4 metres for a detached property
  • No conservatory/extension is built forward of the principal elevation or side elevation fronting a highway
  • Forbidden building of rear extensions that are bigger than a single story, of exterior cladding and side extensions on designated land


If you live in a listed building, you will require Listed Building Consent.


Building regulations will typically apply to conservatory construction, however conservatories may be exempt from building regulations if:

  • The conservatory is constructed at ground level and is less than 30 square metres in total floor area.
  • The conservatory is separated from the house by external quality walls, doors, or windows.
  • There is an independent heating system with separate temperature and on/off controls.
  • Glazing and fixed electrical fittings comply with the applicable building regulations requirements

It is advised that you do not construct a conservatory if it will restrict ladder access to windows serving rooms in roof or loft conversions, especially if the windows are placed to aid rescue or escape in the event of a fire.

Any new structural openings between the conservatory and property will require building regulations approval, even if the conservatory is an exempt structure.

How Much Does It Cost to Build a Conservatory?

As with any construction job, cost is a major factor that should be considered right from the start. Understanding the potential posts of your conservatory build will help you to form a practical plan for your budget and spending.

According to Price Your Job, the average rate a conservatory specialist will charge is typically around £150-£200 per day in labour. This means that with a team of 2-3, an average sized lean-to conservatory will generally take around 2-3 weeks to build, costing a total of £6,000 - £10,000 for labour.

The cost of materials will differ from project to project depending on the size and type of conservatory, number of doors, glazing types, quality of materials etc. However, on average material costs typically start at around £2500-£4000 for a smaller lean-to structure and reach up to £8000-£10,000 for larger Victorian and P-shaped conservatories.

Let’s say a 3.5m x 3.5m lean-to conservatory may total to £8,000. Breaking that down into individual costs, you will probably be spending around £3200 on materials and supplies, £4400 on professional trade hire and another £400 on waste removal.

Remember, you’ll also need to factor in any additional costs to the budget such as potential building regulation costs, guttering, blinds, flooring, heaters etc.

If you are planning to install a new conservatory yourself, the following are some rough supply costs you could expect to pay:


Type of Conservatory

uPVC Supply Cost (m²)

Wood Supply Cost (m²)

Aluminium Supply Cost (m²)


£360 - £700

£760 - £1080

£440 - £820


£530 - £760

£550 - £1125

£620 - £870


£300 - £490

£480 - £1320

£320 - £580


£430 - £480

£610 - £700

£530 - £820


£690 - £980

£630 - £930

£810 - £1120


£690 - £980

£610 - £700

£810 - £1120


£850 - £4980

£1150 - £1840

£1000 - £5570


Check out How Much Do Conservatories Cost? for a full run-down of every potential cost you may be faced with in your conservatory construction project.

How Long Does It Take to Build a Conservatory Yourself?

Of course a big thing to consider when taking on a project such as this, is how long construction will actually take. The last thing you want is to be stuck with a half-finished conservatory because you ran out of time.

The total duration of the job will depend on a few different factors such as your level of experience, the size and type of conservatory you are building, the condition of the area in which you are building and even the weather. However, to give you a rough estimate of the timescales you could be looking at, we’ve broken each stage of the construction process down into estimated time periods, for a single confident DIYer tackling the job:

Digging & Laying the Base – 2+ Days

The duration of this stage will really depend on the type of foundation you opt for. Digging and laying a full concrete foundation can take anywhere up to one week, however with the use of specialist pre-fabricated bases, this can be cut down to around 2 days.

Adding Frames, Doors & Glazing – 1-2 Weeks

It is important to take your time when adding in walls, framework and glazing as poorly measured/installed frames will hugely impact the structural quality and safety of your conservatory.

Walls, frames, doors, and windows can take up to a week or two for very complicated builds, however, may take less for more simplistic structures.

Building the Roof – Few Hours – Few Days

Once again, careful installation of your conservatory roof is key to prevent future weather damage and leakages. Dependant on the type of roof structure and the dimensions, a conservatory roof can be installed in anywhere from a few hours to a few days on average. Bear in mind that heavily insulated roofs/traditional tiled roofs can take longer.

Finishing Touches – 1 Day – 1 Week

Once construction is complete, it’s then time to add the final finishes. This includes laying flooring, painting walls, introducing décor, and adding fittings such as ceiling fans, blinds, curtains, lights etc.

The timeframe for this well really depend on the internal size of your conservatory and the type of finishes you choose. With this taken into consideration, you may need to set aside anywhere from one day to a full week for this finishing stage.

Thinking of Building Your Own Conservatory?

If you are thinking of starting your very own conservatory construction project, why not take a look through our extensive selection of high-quality conservatory roofing materials to get you started.

For further help,  get in touch with our friendly customer service team who will be more than happy to help. Simply give them a call on 01295 565 565, email [email protected], or leave a message in our handy live chat.