Tuin Log Cabins: Interlocking Log Explained

NattyShedGirl Cabins, Reviews Leave a Comment

Wait a minute?! What is interlocking log?

I know, I’ve been asking myself the same thing. How do I explain, not only what it is –  but why is it a thing? And how do Log Cabins compare to Sectional Panels?

Cath my saviour, from the Gillies and Mackay office messaged me last week to say,

‘Oh beautiful one of beauty like no other…. People keep bringing Tuin Brochures in?! Can you please bestow your knowledge of Interlocking Log and what I need to know to help our customers make the best buying decision – for them.’

So what is it?

Interlocking log is;

Machined logs or battens, half notched (cut out) at the corner, interlocking with the opposing wall. Each log is scribed (tongue and groove) to fit the log below.

Interlocking log buildings have no wall frame. The thicknesses range from 28mm – 100mm.

It’s quite a nifty little number and is based heavily on the traditional crafting of REAL log cabins. REAL log cabins are made from felled trees (hand picked) and notched as they are, in full trunk form to slot together to form full walls and gables.

Grant’s got a REAL log cabin in his front Garden.

Grant's Real Log Cabin, Garden Room

Grants REAL Log Cabin

How did he manage that?

Grant spent a fair bit of his youth in the Canadian Northern Hemisphere as a lumberjack, logging and building cabins just like this.

When Grant returned to Scotland, back in the 80’s he started building himself a log cabin to live in.

Grant’s Log Cabin spent a fair few years as the Gillies and Mackay Office (the good ol’ days) until we built our new show area.

Now that Grant has a family, his Log Cabin is namely for sleepovers and parties of course!

Over the years we have been asked to make REAL log cabins, but people are quickly discouraged with the time they take and evidently the cost involved.

Although there are many Interlocking Log wholesalers on the market, we’re going to focus on TUIN – given their close relationship with Cath in the office. 😉


Tuin Log Cabins Website Page

Screenshot from the TUIN Website

I was reading Tuin’s take on materials… Now normally I’m not all bitchy and jumping on other people’s efforts BUT!

Tuin’s ‘cheap log cabin’ page sounds like the person who has written it, is smashed out their face on hallucinogenic’s. Have a read. 

Addressing your reading audience as ‘kind sir’ is never going to float with me.  

Although in saying that Tuin are actually writing content that’s for their audience rather than themselves, which needs some credit for sure.


Tuin said something I definitely did not agree with – Spruce being better than Pine #RollingEyeEmoji

We’ve talked about Spruce before – we know it’s a whitewood and we also know whitewood (regardless of origin) isn’t going to be as good as Northern Scandinavian Pine.

Granted Tuin may be using Northern European Spruce which will count towards slow growing, and may well be the ‘better’ whitewood than it’s other European counterparts…

But… It is categorically NOT better than Northern Scandinavian Pine.


We know this, because we buy Russian Spruce. And that Russian Spruce is real good but not as good as our Scandinavian Pine (Redwood).

Russia and Northern Scandinavia are within the Arctic Circle. The most northerly of the five major circles of latitude.

Northern European is a bit vague. If I were asking about timber I’d want to know if it came from the Arctic Circle. Maybe Tuin can clarify this?

Here’s the type of badge you’re looking for when dealing with Timber Building Company’s.  

Arctic Circle Marking on Tarp

Straight from the Arctic Circle

Tuin just got it tight there so let’s look at what Interlocking log does right?

Tuin Log Cabin

Screenshot from TUIN website

(TUIN Dyre Build)

The building pictured is under £2000.00 (27th June 2018)

Here’s some TOP FACTS about Interlocking Log that have changed the Outdoor Building world.

Interlocking Log has revolutionised self build for the average Sally and Bob. It’s basically a massive jigsaw and with the right patience and aptitude (determination) can be done by instruction fairly pain free.

It’s a much cheaper alternative, (cabin wise) if you’re building within Permitted Development and don’t require Building Control.

The thermal efficiencies of the thick log are intended for greater warmth in the winter and cooler in the summer.

That’s enough Top Tips -what does it do?


Interlocking log has been a huge success in consistent climates. And there’s a reason Log Cabins are meant for the Northern Hemisphere – it’s just cold.

Whereas in Scotland, we do get some decent mild weather along with some bitter cold winters. This causes timber to shift, split and bow.

And when your timber is 70mm thick, the shifting, splitting and bowing is severe.

Wind and water tight it may have been on turn of purchase but after a couple of years exposure, movement can become detrimental to the building and your use of it.

Of course, if your interlocking log was a wee DIY project,there are certain hacks to stop it from shrinking beyond use that you’ll be able to do yourself… But this all depends on the timber it was originally cut from.

As the saying goes; there’s no saving shite wood in a sinking ship*…

Scotland’s climate has caused us at Gillies and Mackay a great deal of heartache over the  40+ years we’ve been at it – none more so than the leaking Garage epidemic whereby water was penetrating through the weatherboard.


Garden Outbuilding, Sectional Building.

Gillies and Mackay Garden Room

But not once did Grant suggest Interlocking log as the solution. Instead we designed the 3 tier and a 5 tier wall specification. Layer upon layer.

This completely revolutionised G&M’s garages to the point where we are now charging 3 x the market value for a product that actually works in Scotland.

3 Tier

  • 19mm thick tongue and groove Scandinavian weatherboard,
  • 22mm breather cavity with membrane,
  • 9mm OSB
  • & 95mm pressure treated framing.
  • (50mm thick wall)

5 Tier

As above plus;

  • 70mm Ecotherm foil back insulation
  • 16mm V’d Redwood Lining
  • (161mm thick wall)

The versatility of sectional construction can also help the customer decide as and when to invest in the next layer.

Given the choice at Gillies and Mackay, we feel, in Scotland – we are far better layering our walls.

Dad doesn’t necessarily agree (he never does).

As we’ve said before the key element here is the quality of timber used in the first place. Interlocking log would do great but the reality is, it’s very unlikely, whether it’s Tuin or any of the other mass suppliers that you’re going to get a timber that’s decent enough to withstand the Scottish climate.

Interlocking log has it’s benefits and it can be a practical solution to your garden room needs, especially if budget is a heavy factor. 

The choice is yours.

Other articles you might fancy reading, ken… If it’s a Sunday and you’re aimlessly trawling the Shed chat.

Shed v’s Summerhouse, what’s the difference?

What to look for when buying a Shed? 

How much does a Garden Office Cost?

Or check out our YouTube channel for HEAPS of videos on all your questions.

Great to chat Fam.

NattyShedGirl x

*Shed 😉