Screwbase Groundscrews

19/05/2026

We had a busy day out today in Bexley, S.E. London.
We didn't just complete the installation of 28 1500mm long groundscrews, we had to conduct the load testing too!
The Structural Engineer called on our knowledge and experience to assess what was needed to achieve the necessary loads, and also to provide a factored load test report to not only prove that the groundscrews will meet and exceed their required loads. The report has to also satisfy building control so that the Garden Room build can continue without delay.
We don't usually load test and install on the same day, but in this case it was a time sensitive job.
We didn't just make the right decision as to the size and quantity of groundscrews required, we did so accurately, meaning our client didn't have to pay for unnecessary works.

I will admit though, we did have some spare groundscrews with us, just in case we had underestimated the requirement! :)

08/05/2026

One of our jobs this week was this one: quite a large groundscrew base with an included floor frame.
Our client had three reasons for choosing groundscrews for his combined shed and music room.
Speed - we were in, job done, and out again in only 1 day and the floor frame is immediately ready to build onto. No waiting for concrete to go off, and.....
Cleanliness - we didn't chew up his garden, and there was no concrete to spill on his drive, or the road.
And the slope - so, as you come out of the clients back door, the back garden slopes from the house backwards and from left to right. If a concrete base had been laid it would have formed a dam across his garden so in the winter wet season, the rain would run down his garden, meet with the concrete base, and run off toward his garage. The garden would be a running, swampy river that would be likely to flood the garage. Groundscrews are typically installed to just above the highest point so any rainwater can just run straight under his shed without making the floor wet.

But what about the cost? The whole of this base project came to around £3,500 +VAT. If concrete had been used (forget about the mess) our client would have had three chaps on site for 3 days. he would have had skips, permits, a shuttering, and concrete to pay for, plus he would still need to spend out for a floor frame - but that floor frame would have been in ground contact and more susceptible to rot.

Groundscrews. they're faster, usually cheaper, and a lot more environmentally friendly than concrete.

27/04/2026

We get asked what the process is?

If your garden building falls into the remit of building control, you are most likely going to be asked for a load test, so thats the first thing that will need to be done. Load testing is done, and factored results are produced, in order to satisfy building control that the groundscrews are going to provide a stable, capable base for your intended structure.

Once the load testing has been completed and signed off, the size and quantity of groundscrews can be calculated and the installation can commence.

The final part of the job is for the floor frame to be installed - we can design and build that for you too, in accordance with the British Standards timber load charts.

the details? Yes, I could go into them here, but they are for us to worry about. That's the whole point of having Screwbase do the job for you. We take the worry away and leave you with a well built, structurally sound floor ready to insulate, then build onto.

Groundscrews made simple.

11/03/2026

A cracking day for installing , possibly the first day this year where we've been working in the sunshine. We had a lovely drive down to Uckfield in West Sussex, and for a change the M25 behaved itself :)
This layout is 8m x 4m, and due to the slope of the ground, we used a combination of 1.25m, 1.5m, and 2.0m groundscrews.
We also performed a to ascertain the load bearing capabilities of each load point. Our client requested this as the needs to comply with the current building regulations

09/12/2025

It's been a great year! We now cannot take any bookings until mid January, but as we get into the new year no doubt the waiting list will extend. If you're looking at starting a garden room, shed, or summerhouse project in the spring, it would be a good idea to consider getting the job scheduled sooner rather than later to avoid unnecessary delays.
This job was over in Pilgrims Hatch, Essex and was a bit on the muddy side! Our job was to install the groundscrews and timber floor frame for a 6m x 6 garden room. As we used 4x2 C24 treated timber for the floor frame, the groundscrews were spaced at no more than 1200mm on centre, ensuring that there's absolutely no flex to the floor at all. The frame has the ring beam doubled up around the perimeter with triple beams across the front. The additional timbers on the ring beam aren't just nailed, they are also glued to laminate the timbers together.
We were a day on site for this one, and the floor is ready for our client to work on immediately

09/07/2025

For a tortoise! This 4m x 3m groundscrew base with a double ring beam floor frame is the start of our client's garden room for a tortoise to live in. This isn't your 25cm long normal tortoise, this one is a giant, over 70cm long!
The only access to this cottage garden was through the cottage which made groundscrews not just the cleanest option, but also, because of the sloped ground, also a very much cheaper option. Groundscrews cost less than half the price that our client had been quoted for concrete.
A good result, and immediately able to be built on.

21/06/2025

An interesting job. This base is 10metres long, 3 metres wide.
When the project is finished it will have three areas: a covered pergola, a hot tub, and a sauna.
The pergola end was installed using 800mm groundscrews. Each one has a load bearing capacity of in excess of 300kg, so there was no need to go deeper at that end. 10 groundscrews giving a speculative minimum load of 3 tonnes will be enough!
In the middle, where the hot tub will go we used 12 groundscrews at 1200mm. - so a minimum of 3.6 tonnes over a 3m x 3m area there!
At the garden room/sauna end theres another 12 groundscrews, this time over a 3.6m x 3m area.
The whole job was designed and positioned to go around 4 massive posts which had already been installed about 5 years ago,
This job was completed in 1 day

21/06/2025

A frame for a pergola, some decking, and a large hot tub!
The groundscrews used for this job are the largest diameter groundscrews we currently install, 1200mm x 76mm.
The reason was the weight!
Our client informed us that their intention was to install scaffold planks as decking boards. Scaffold planks are about 75% thicker than normal decking boards, that weight had to be accounted for.
The hot tub going on to the deck has a static weight of 1,670kg, plus however many people are in it.
Then there's a pergola going over the top.
Our solution was to install 16 groundscrews, each being able to take over 500kg in weight. As well as installing groundscrews, we also load test them to give their factored load capabilities. The absolute worst result we have had from a 1200 x 76mm groundscrews is 536kg, so with 16 groundscrews of that size being used, the load capacity will easily exceed 8 tonnes. Although we didn't load test this installation, judging by the way the installation machine struggled to get the groundscrews in, I wouldn't be surprised if these ones wouldn't test to well over a tonne each!

Over the top of the groundscrews we installed a pressure treated, 47mm x 95mm floor frame with a double ring beam which was both glued and mechanically fastened together.

Installation time: 4 hours

21/06/2025

How about a base for a Dunster House log cabin, built onto groundscrews!
Our client for this job can only access the garden through her house, so concrete would have been a very messy, very expensive option. In order to lay the concrete, first the topsoil has to be removed from site. This would have meant wheelbarrowing all the soil through her rather beautiful kitchen.
Back filling the base would have meant all the hard core being wheelbarrowed in, and then hiring a concrete pump to get the concrete to the back of the garden. The quotes she received for this work were in the region of £3,000

We carried the groundscrews and floor frame through the house, There was no mess and no damage!
The installation took less than 4 hours, the cost was just over £1,500

As this will have a log cabin on it, a double ring beam frame is needed. The inner ring is to fix the floor boards to, the outer ring is for the structure of the log cabin to sit on.
Perfectly level, ready to build on.

21/06/2025