Blackstone Garden Rooms


Blackstone?! Send me a brochure

So you're needing a space - for whatever it may be there are certain things that it definitely needs to do.

This space will need to keep you warm and dry. It will need light, electrics and maybe even water. It will need to be practical and usable for what you want to use it for. 

Whether it’s work, play or a place for guests to stay, the Blackstone Garden Room range from Gillies and MacKay has all of this in mind when it comes to designing and building your perfect Garden Room.


Over the years we have identified 3 main reasons


“So much space for activities!” 

Don’t get me wrong, you love them with all your heart. But, jeez we all need our own space right? 

Whether it’s ‘never leaving home children’ or your mother in law coming to stay, a Blackstone Garden Room is the ideal Annex solution for housing the whole family


the crail garden room

Do not distrub, artist at work. 

Creatives LOVE a Blackstone. Painters, Crafters, Writers and Musicians all need somewhere to go to be amazing at what they do best.

 We know things like; lighting, sound, warmth and practicalities are so important when designing your space and that’s why we do it from scratch, for you. 


Blog feature image for "What Kind of base do I need for a Garden Room"

A Blackstone that pays for itself!

The working space for you to share your gift. Things like beauty therapies and holistic treatments are fairly traditional working from home businesses, but maybe it’s personal training, a photography studio or a dog grooming stand?
Whatever it is, a Blackstone gives you the opportunity to do it so much better.  

Make up

Specification is what makes Gillies & MacKay really special. We like to get specific 🙂


19mm Scandinavian Pine redwood tongue and groove weatherboard. We love our redwood, but there are other options, like Larch and Cedar for those with a bigger budget. 22mm breather cavity with membrane and 9mm OSB bracing. 95mm x 45mm pressure treated framing. 70/100mm Ecottherm Insulation. 12.5mm Plasterboard & 16mm redwood V’d lining.


Framing ranges from 95mm x 45mm to 180mm x 45mm, it depends on the size of the building and whether or not Grant feels the need. It’s the same with the insulation. I like to put 100mm in the roof and floor to cozy the heat in, but depending on your budget you may be happy with just the 70mm. We work the cavity through the roof, like the walls and use a Proctorshield membrane which is specific for roofs. There’s a few options for the covering. Most opt for either the Steel Box Profile or the Bitumen Shingles. It really comes down to your own preference.


70/100mm Ecotherm Insulation, 19mm tongue and groove redwood flooring and 95mm x 45mm framing. fairly straightforward. We love to use laminate for finishing too. The good stuff – QuickStep.

picture of the inside of the studio


Electrics, decorating and finishings, we’ve got you covered. Depending on location, we can arrange to have our electrician visit you and talk through everything you require. A decorator is needed for aimes taping if you opt for plasterboard. If you’re going for V’d lining you may manage the interior yourself or again, we can arrange a decorator to carry out the works for you.

How much does a Garden Room cost?

Size plays an important part to the cost structure of a Blackstone. As does, utility. If you’re planning on the building being bigger than 30m2 or running mains water to the building, it will require a Building Warrant and Engineers Certification. This can add a considerable amount to the cost. As you can see below the Annexe pricing is far greater than the the others.

Examples of things we cost for:

  • Planning / Building Control 
    (in few cases required)
  • Site Preparation & Basework 
  • The outer body 
  • The inner body 
  • Roofing 
  • Windows
  • Doors
  • Internal Finishing
  • External Finishing
  • Verandah
  • Heating
  • Electrics
  • Decorating

Small building

£12,000 – £15,000

Medium building

£15,000 – £25,000

Large building

£25,000 – £40,000

How much does it cost to install a medium-sized garden room blog feature image
Buyers Prep
Cara Mackay

How much does it cost to install a Medium-Sized Garden Room?

Dog grooming. Personal training studios. A place for you and your friends to hide from the kids and drink some prosecco. Whether you need space to turn your passion into profit. Or you just need somewhere to unwind and chill out with friends, a Garden Room will do the trick. A Garden Room is the (even) cooler big sister of

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How much does a small Garden Room cost - blog feature image
Buyers Prep
Cara Mackay

How much does a Small Garden Room cost?

You need more space. A nice quiet space. Somewhere away from all the noise, the never-ending laundry pile and the constant bickering over who gets control of the remote. Maybe you need somewhere to channel your inner J.K Rowling. Or a place to run your business empire that isn’t overrun with dirty dishes. Maybe it’s not even for you, but

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'Andrews' style garden room in green
Garden rooms
Cara Mackay

What is the best size for a Garden Room?

So many factors will play on what size of Blackstone Garden Room you will want. Primarily, it will come down to the space you have and to what extent you want to build to. For example, it’s purpose: if you intend to use your Blackstone as a holiday let then it’s going to be bigger than if you’re just thinking

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Blog feature image for "What Kind of base do I need for a Garden Room"
Garden rooms
Cara Mackay

What kind of base do I need for a Garden Room?

At Gillies and Mackay our buildings are fairly HEFTY, to say the least. So, when we’re thinking about the foundations for a Garden Room, we need to appreciate that the weight has a huge influence over what kind of base we should construct. Typically a Garden Room will weigh over 2 tonnes. We would normally recommend a concrete plinth built

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