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Our New Garden Rooms
(Under 12m2) Specification

This article is about our former summerhouse specification, which has since been replaced by our brand-new Garden Rooms (under 12m2). It's worthwhile reading, but to jump straight to learning more about the new spec, click on!

We put a lot of love and hard-work into our buildings and customer care. At Gillies & Mackay we manufacture and assemble our own timber buildings from our workshop in Errol. 

And with that comes with a price tag💰 We don’t shy away from the fact that we are more expensive than many other garden buildings available. 

But you might be wondering:

“What am I really paying for? And what factors impact the pricing of a G&M building?”

For us, the quality materials that we use to create our buildings contribute to the cost. In fact, our materials equate to roughly 65% of all of our costs. 

Making a choice between ‘that’ll do’ and ‘that’s better’ is something you need to decide based on importance and value to you and your needs. 

For Gillies & Mackay it’s always been about ‘that’s better’ and we are very particular about our suppliers for G&M – which does make our buildings more expensive.

Related content: Gillies & Mackay pricing page

A photo of a pale green Rannoch summer house in a garden. It sits next to a hedge and a wall on a slabbed patio next to a lawn and a tree.

What timber do we use in your G&M building?

The timber we use is extremely important. We put a huge amount of trust in our suppliers, to ensure that the wood we are provided with is to the highest of standards.

Let’s explore the timber we use in a little more detail. 

Cladding; Tongue and Groove Weatherboard Kiln Dried* Dressed Scandinavian Pine (Redwood)

At Gillies and Mackay – it’s easy, all our cladding is 19mm (dressed, as it comes to you) thick or thicker. 

*Kiln Dried is basically a big oven that speeds up the drying process for fallen timber. The less moisture content the wood has the better it is for using as timber structures. 

**Dressed just means they’ve made it pretty 😉 planed it down to a smooth finish. It’s important to note the measurement of dressed vs cut size. For whatever reason, I presume because as manufacturers we pay a premium to have our wood dressed, some Shed builders will advertise the sawmill size? No the actual size you get. For example,  they’ll say 16mm thick but it’s actually 14mm thick. 

A close-up photo of a timber-clad building, showing tongue and groove cladding.

Framing; Regulated C24* Eased Edge & Celcurised** 

We use pressure treated timber for all our exposed wood (floor joists, bearers, donks (roof strips)) and for the internal frames of our Sheds and Garages. 

For our Garages and Garden Rooms we also use pressure treated weatherboard as standard because of their 3 tier wall make up.

*C24 means the timber is graded and certified to withstand specific loadbaring, the higher the grade the wider the span/length can be used – C24 is a grade of timber used for building houses. 

**Celcurised means that the timber is also pressure treated (green) which protects the timber from the inside out, Celcure is a chemical treatment that protects the timber against Rot, Fungi and Insects. 

Related content: A guide to wood in your shed; weatherboard, sarking, studs and bearers

A photo of the interior of a timber summer house.

What roofing do we use in your G&M building?

The roof keeps out the weather, so we need to make sure we use the right materials, to ensure it lasts a long time. There are a couple of different options for your G&M building roof:

  1. Felt roofing
  2. Steel Box Profile Sheeting
  3. Bitumen Shingles

Firstly, we’ve got felt roofing. Or polyester based SBS180 to be precise. 

A photo of a shed roof. It has roofing felt as its roofing material. There are trees and a blue sky in the background.

There is a long standing ‘discussion’ shall we say, between the superiors at G&M. Some believe felt on Apex Sheds should be the norm. It gives a neat finish, provides the durability expected (10 years) and is hand tacked directly to the roofing boards allowing the tar side to bond to the wood (which creates a seal).

Others in G&M, don’t have the time of day for felt, they’d much prefer to use Steel Box Profile Sheeting on any pitch because of its guarantee and assurance there is no water ingress to be had whatsoever. 

The felt lovers just think Steel looks a bit shite on small Sheds and won’t hear any of it. 

All in all, both have their advantages.

Felt has become increasingly more and more expensive, and the perks of the simple installation are no longer so perky since we don’t do them as often. 

We had been using Steel Box Profile on our big builds for years, things like Garages and Garden Rooms but it was introduced as standard for Pent Sheds a couple of years ago when I was fed up of using Felt on the sloping Pent roofs. The Pent pitch had a tendency to let water sit on the seams allowing water to run back up the cap. Not cool. We had also monitored its behaviour on large Sheds and decided they would only be done in Steel Box Profile too. 

A photo of the gable end of a garden room. It has steel box profile roofing, timber cladding and french windows and doors.

There is a fair price difference between Steel and Felt but vs the return visits to a problem that had no solution other than to reroof in Steel – it seemed only sensible just to go for the Steel and ensure the longevity of our build. 

As it stands now, our buildings come with steel box profile roofing as standard. This roofing is guaranteed for 20 years and has a life expectancy of a whopping 40 years!

All except the Shaped Summer Houses which are a completely different Shed game altogether. They are treated to some right fancy Bitumen Shingles. Because of the shaped roof pitch and the way in which they are fixed, the Shingles are a welcome specification, durable (15 years) reliable, and PRETTY!! 

a photo of a grey and blue 5-sided summer house on a timber deck. There is a deck chair and two potted trees outside.

What ironmongery do you use in your G&M building?

Everything from the felt tacks to the 5 lever locking system in a set of Mortise and Tenon Doors is crucial to the working ability of our buildings. 

The man in charge is Dean and he does not suffer fools gladly. 

When it comes to procurement Dean is one step ahead of any sales rep or supplier. He does his research, he tests, he compares. Dean knows we’ll never have Ironmongery like the ‘old days’ and since everything is imported (mainly from China) we need someone who takes on the challenge to get the best for your money. 

It’s a hard compromise, we’re joiners and we make 90% of the building by our own hands so when it comes to the Ironmongery it’s always a heavily scrutinised area – 

Thanks again to amazing suppliers like SIIS in Fife and our long-standing saviors Prisma down South, we are looked after, and the relationship between them Dean, and G&M as a whole is a trusting one. We know they’re doing their best by us and you by sourcing Ironmongery fit for the longevity of a G&M build. 

Why is a Gillies & Mackay more expensive?

So there you have it. When you buy a G&M building, you are paying for quality materials, alongside handcrafted timber buildings that last a generation.

All this comes with a price tag 💰

If you want to download our pricing guides, then you can take a look at our pricing page here, and find out everything you need to know.

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