The best building supports, compared.
Top pick: LLB 4-pack bolt-down post support Best value: 5-piece decking pedestal, 30–60 mm – Lowest shelf price in the set at about £10.98, with at least 10 reviews and a rating of at least 4.0. 4.6 from 12 reviews. The title height is 30–60 mm. Updated 22.10.2026.
A building support is a small fitting that holds a timber post, a deck or shed joist, or a board while you fix it. Shoppers on amazon.co.uk are mostly raising a pergola post off a concrete pad, levelling a shed or a low deck, or working alone with a cabinet or a plasterboard sheet. A 75 × 75 mm top plate does not cover a 100 mm post. A seller line that says galvanised, or a kilogram figure, is not a design load and not EN ISO 1461 unless the listing cites it. Stars describe light garden frames and shed bases, not balconies. How to choose family, height and fixings is in the [building support buying guide](/hub/diy-supplies/building-support/sub/building-support-buying-guide). The three jobs do not share one product. An elevated post base bolts down and screws to a stand-off so the end grain stays off wet concrete. A decking pedestal is a polypropylene screw foot under a joist, used on an existing hard surface. A telescopic prop is an alloy rod with pads, for holding a cabinet or a sheet while the real fixing goes in. It is not an acrow prop, and it is not falsework.
A building support is a small fitting that holds a timber post, a deck or shed joist, or a board while you fix it.
38 products checked · 61 hrs invested · +22,800 readers
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Personal buying guide
Question 1 of 2
What are you holding?
LLB's four bolt-down supports are 80 × 80 × 250 mm in 4 mm galvanised sheet, with an M24 bolt and a stated pattern of eight 11 mm holes and eight 5 mm holes. The amazon.co.uk line is 5.0 from 13 reviews, and five of the six texts are from the United Kingdom. Reviewers used them to level a shed base and to hold newel posts on a patio over a brick wall, where the adjustment made the drilling worthwhile. The included-components line is No, so anchors are not in the box. One review says drilling the centre-bolt hole was awkward without a jig. Outdoor use is a listing question the bullets do not answer, and no load is stated. At £49.99 it is the tall U-shaped support in this set for an 80 mm post and a 250 mm overall height, and a poor substitute for a plastic joist foot or for an unrestrained fence post.
Pros
Cons
Best for: You want a bolt-down U support about 250 mm tall for a shed or a restrained newel, and you will drill the centre hole with care.
Less suitable: A joist on a pedestal, a free fence post, or a job that needs a large review sample.
Specifications
Common questions
What size is each support?
80 × 80 × 250 mm, in 4 mm galvanised steel sheet. The bolt is M24. There are 8 holes at 11 mm and 8 holes at 5 mm.
Is the height range given?
The title says adjustable. The only height figure is a total height of 250 mm. No minimum-to-maximum range is printed.
Are fixings included?
The included-components line says No. One review says drilling the centre-bolt hole was easier with a jig, which is not in the box.
Aleawol's two carbon-steel bases are the taller post jack in this set, threaded from 15–23 cm, with an upper plate of 8.3 × 10 cm and a lower plate of 10.5 × 10.5 cm. The shelf price is £25.99. The amazon.co.uk line is 5.0 from one review, and the saved listing contains no review text, so that star is not evidence of a finished pergola or shed. The bullets name a pipe wrench to turn the screw, matching screws whose type and count are not specified, and an anti-rust coating rather than a cited EN ISO 1461 batch. The listing question on maximum weight is unanswered. Named uses include sheds, balconies, carports and fences, which is a wider claim than a two-piece jack with no published capacity can carry. Buy it only after you have measured a 150–230 mm gap and you will judge the steel yourself. Leave it if you wanted UK reviewers describing rust, threads or the screw pack.
Pros
Cons
Best for: You have measured a 150–230 mm gap under a restrained post and you will inspect the coating and the screws yourself.
Less suitable: You are choosing on stars, or the job is a balcony, a carport or a free fence post.
Specifications
Common questions
What is the height range?
15–23 cm, turned with a pipe wrench. Anti-loosening nuts lock the height. The listing does not say whether you can adjust them after they are fixed.
What is the stated load?
None. The listing asks for the maximum weight capacity and does not answer it.
How many reviews are in the saved listing?
The amazon.co.uk line is 5.0 from 1 review. The saved listing has no review text.
AHAQU's black four-pack uses the same 100–150 mm band, with a 75 × 75 × 3 mm upper plate and a 95 × 95 × 2 mm lower plate, at £23.99. The listing line is 4.8 from 92 reviews, and 22 of the 28 texts in the file are from the United Kingdom. Buyers levelled a lean-to gazebo, a new shed base and small concrete pads under a timber conservatory, and one jacked a sunken kitchen kickboard by about 2 mm. The bullets name 16 screws, while the included-components field still prints 1, so the box is not a confirmed concrete-anchor kit. A UK review of a gazebo on 70 mm corner posts found too much movement and called it a light structure only. The first turn of the thread can be stiff, and no load is stated. Choose it when the post is restrained and the plate covers that timber, and leave it when the frame has to carry a heavier roof on these feet alone.
Pros
Cons
Best for: A light restrained post or shed corner on a pad, where a black finish matters and you check the screws on arrival.
Less suitable: A heavier gazebo, or any job that needs a published capacity.
Specifications
Common questions
Are screws included?
The kit bullet says 4 supports and 16 screws. The included-components field only prints 1. The listing does not say the screws are concrete anchors.
What plate size is the top?
75 × 75 × 3 mm on the upper plate and 95 × 95 × 2 mm on the lower plate. Height adjustment is 100–150 mm.
Can they be used outside?
The bullet says everyday outdoor use around decking, fencing and garden structures, with a black finish on galvanised steel.
QWORK's black four-pack extends 100–150 mm, with a 75 × 75 mm upper plate and a 95 × 95 mm lower plate, at £20.98. The listing line is 4.8 from seven reviews, and the file has three texts: one from the United Kingdom, one from Belgium and one from Germany. The UK review calls it a solid support leg at a reasonable price, and the Belgian review calls it stable. The German review says the steel is painted and therefore not corrosion-free, which sits beside a material field that says alloy steel, bullets that say galvanised, and a finish field that says polished. Fixing screws are mentioned in a bullet and are not a named included component, and the question about screws is unanswered. No load is stated. It is a cheaper black 100–150 mm four-pack than FWEEK or AHAQU, and a weak outdoor pick if you needed a coating you can name or more than one UK review.
Pros
Cons
Best for: You want the lowest four-pack price in the 100–150 mm band and you will check the coating when it arrives.
Less suitable: You want a large UK sample, or a coating cited to EN ISO 1461.
Specifications
Common questions
Are they galvanised?
The title and bullets say galvanised steel with an electroplated finish. The material field says alloy steel and the finish field says polished. One review says the steel is painted and not corrosion-free.
What is the plate size?
Upper 75 × 75 mm and lower 95 × 95 mm. The height range is 100–150 mm.
Are screws included?
A bullet says they are easy to install with fixing screws. The listing question about screws is unanswered, and screws are not a named component.
The Ceta pack is ten polypropylene pedestals whose title covers 60–140 mm, and UK reviewers use them to level shed bases and deck joists on uneven concrete. Across 211 amazon.co.uk reviews the line is 4.6, and the 50 texts in the file are all marked United Kingdom. One buyer left a 12-foot shed standing after a year with the feet about 300 mm apart, and another built a 4.2 m by 3.6 m floating deck on 28 pedestals. You set the top collar, screw the head down, then fine-tune at the base, because the height cannot be finished only after the joist is fixed. Several reviews say no screws or bolts were in the box, and one says a plastic fixing tab breaks if you drop it. A review says the head centres a 45 mm beam and struggles to centre a much wider one. The seller line of 1662 kg/m² at 6–8 supports per square metre is not a test in this file. It is the top pick here for a joist on a hard pad when you want the largest UK review sample, and you should leave it for a post end or for a gap outside that title band.
Pros
Cons
Best for: You are raising joists for a shed or a low deck on a hard pad, and you will buy the screws yourself.
Less suitable: You need a steel plate under a post end, or a gap outside the 60–140 mm title.
Specifications
Common questions
What height does this pack cover?
The title says 60–140 mm. The bullets also list 18–30 mm, 30–60 mm and 60–135 mm. The material field prints 60mm-135mm, which is a height, not a material.
Are screws in the box?
The included-components line names a decking head. Several UK reviews say no screws or bolts were supplied.
Can you adjust the height after the joist is fixed?
One UK review says no. Set the top collar close to the height, screw the head down, then fine-tune at the bottom.
FWEEK's four galvanised bases extend from 100–150 mm, and reviewers use them to lift garden-arch and pergola posts off a concrete pad so the end grain is clear of the wet surface. The amazon.co.uk line is 4.6 from 169 reviews, with 46 texts in the file from the United Kingdom and France. The upper plate is 75 × 75 × 3 mm and the lower plate is 95 × 95 × 2 mm, so a 100 mm post overhangs the top. One UK review says the machine screws in the box were no use as concrete anchors and that extra bolts were bought. Another called the metal flimsy, under 2 mm, and said the 100 and 150 figures are the height range, not the plate size. Threads are described as poorly cut, one unit arrived scratched and already rusting, and the listing does not state a load. It suits a light restrained frame on a pad if you supply the right anchors, and it is a poor match for a free fence post or for a job that needs a published capacity.
Pros
Cons
Best for: You are raising a restrained pergola or arch post 100–150 mm off concrete and you will buy the anchors.
Less suitable: A 100 mm post that must sit fully on the plate, a free fence post, or a balcony load.
Specifications
Common questions
How far do these bases extend?
The listing says 100–150 mm. The upper plate is 75 × 75 × 3 mm and the lower plate is 95 × 95 × 2 mm. One review says those 100 and 150 figures are the height, not the plate size.
Do they come with concrete screws?
The included-components line does not name screws. Reviews say the supplied screws were the wrong type and that concrete anchors were bought separately.
Is a load given?
No. The listing has no load figure, and one review says the load was not stated.
This five-pack of polypropylene pedestals is titled 30–60 mm and is the lowest shelf price in the set at £10.98. The amazon.co.uk line is 4.6 from 12 reviews, and the file holds two United Kingdom texts. Both reviewers talk about packaging and a first impression of strength, and neither describes a finished deck. A bullet also prints styles of 60–140 cm and 30–60 cm, which clashes with the millimetre title, so measure the gap against the title band. No load figure and no screws are stated. One of the two reviews calls the pack possibly a little overpriced even while scoring it highly. It is the best value pick here as the cheapest pack with at least ten reviews and a rating of at least 4.0, and a weak pick if you need a shed that reviewers have already left standing.
Pros
Cons
Best for: You need a few low risers for a small gap on a hard pad and you accept a thin review file.
Less suitable: You want a 60–140 mm range, a large UK sample, or a worked example of a finished shed.
Specifications
Common questions
What height is this five-pack?
The title says 30–60 mm. One bullet prints two styles as 60-140cm and 30-60cm. Those units are not the same as the title.
What are they made of?
The bullets say premium PP that is UV resistant. No load figure is given.
Are instructions included?
The listing asks and does not answer. No instructions are named in the included components, which are five pedestals.
UGEBROGH sells 24 low-profile polypropylene pedestals, printed as 30–60 mm and also as 1-3/16 inch to 2-3/8 inch, for floating deck joists, a patio or a shed. The listing line is 4.5 from 11 reviews, and all nine texts in the file are from the United Kingdom. Reviewers turned the collar to level joists on an uneven slab without timber shims, and one said a 24-pack covered about a 2 m by 2 m area for small steps of height, at about £1.67 each. The collar becomes very stiff under a heavy joist and needed grips. Hollow bases filled with rainwater before the boards went on, and the lowest setting still adds about an inch, which is too much where the clearance is tighter than that. No load figure is given, and screws are the fixing method rather than a listed component. At £43.99 you are buying count and a low band, and you still need a hard surface that is already close to level.
Pros
Cons
Best for: A small low deck or shed frame on uneven paving, where 30–60 mm covers the whole gap.
Less suitable: A clearance under about an inch, or a joist that needs the 60–140 mm band.
Specifications
Common questions
How high do they go?
The listing says 1-3/16 inch to 2-3/8 inch, also printed as 30–60 mm. One review says the lowest setting still adds about an inch.
Which joists do they fit?
The bullets name 2×4 and 2×6 framing and wood, composite, WPC and aluminium decking. No load number is given.
Do you need concrete?
The bullet says no excavation and no heavy concrete blocks: position the pedestal, adjust the height, and screw the joist. Screws are not listed as supplied.
Eummy's pair of telescopic rods runs 30–59 cm and is sold as a third hand for cabinets, plasterboard and glue-ups, with a seller load of 40 kg that is not a test in this file. The listing line is 4.2 from 102 reviews, and 22 of the 23 texts are from the United Kingdom. Reviewers held kitchen wall units, panels while glue cured, tiles, and a cistern after the mounting screws failed. The pair is £15.99 and the file lists 1.16 kg, with nylon anti-slip pads that rotate. One review says the handles broke within a few months, another could not tighten the locking nuts, and another says the rods slid under the weight of kitchen wall units. End caps are fiddly, and no carrying case is stated. Use them to hold a light board while the real fixing goes in, then take them down once the bracket holds. They are a poor stand-in for an acrow prop, and the wrong length when the gap is a ceiling rather than a wall cabinet.
Pros
Cons
Best for: You are fitting wall cabinets or a plasterboard sheet alone and the gap sits inside 30–59 cm.
Less suitable: A structural shore, a heavy board, or a ceiling height this rod cannot reach.
Specifications
Common questions
How long are the rods?
The listing says 30–59 cm. The seller load is 40 kg. That figure is not an independent test.
Can they hold a wall cabinet?
Cabinets are named in the application bullet. UK reviews use them for wall units. Other reviews say the lock slips or the pads slide under a kitchen cabinet.
Is a carrying case included?
The listing asks the question and does not answer it. No case is in the bullets.
Dandelionsky's pair is titled 50–115 cm for plasterboard, cabinets and similar holds, at £25.98, with the same 40 kg seller line as the shorter Eummy rods. The listing is 4.1 from 23 reviews, and the file has five United Kingdom texts. One held tiles on a window reveal through a timber batten until the adhesive set, and another levelled kitchen wall units so the brackets could be marked. A bullet also prints 30–59 cm or 50–115 cm, and the product-dimensions line prints 1 × 1 × 1 cm against a stated weight of 1.8 kg, so those size rows are not a tape measure. There were no instructions in one review, and that buyer could not lower the top section. End plates are hard plastic in a review and slipped on tiles, and another says the extender does not tighten and slips under load. Use the title length for a taller solo hold, then remove the rod once the fixing takes the weight. It is a poor pack if you needed a grip pad on tile or a leaflet that shows how the inner tube comes down.
Pros
Cons
Best for: A gap inside 50–115 cm while you fix a cabinet or a tile batten, if you can work out the lock.
Less suitable: Tile work that needs a grip pad, or any load you would treat as temporary works.
Specifications
Common questions
Which length is this listing?
The title and the size field say 50–115 cm. The bullet also prints 30–59 cm or 50–115 cm. The product-dimensions line says 1 × 1 × 1 cm.
What load is stated?
40 kg, as a seller line. It is not an independent test.
Are instructions included?
Not in the included components. One review says there were no instructions and the top section could not be lowered.
INCENDIOS sells two cabinet jacks whose title runs 120–290 cm, with a seller figure of 70 kg in the bullets and 69.85 kg on the load-capacity line, plus TPR pads of 12.5 × 8 cm and an Oxford bag. The shelf price is £45.99. The listing line is 4.0 from 26 reviews, with seven United Kingdom texts and eleven from the United States in a file of 18. UK reviewers used them to hold timber while gluing or screwing, including a door frame, and one used them to spread floor joists, with the caveat that they are not heavy duty. A plastic screw clamp slipped and one UK reviewer added a G-clamp. One UK review describes poles that telescope from 30 cm to 60 cm, which clashes with the 120–290 cm title, and several US texts describe a much shorter range. The file does not say which length that UK buyer received. Treat the title as the order and measure the closed tube before you rely on it for a high ceiling. In the reviews they are a third hand for plasterboard, and a poor choice as an acrow prop or as a post base.
Pros
Cons
Best for: You need a long third hand for a sheet or a cabinet and you will measure the closed length when it arrives.
Less suitable: Falsework, a heavy board, or a job where every review must already match the title length.
Specifications
Common questions
How long is the pole on the listing?
The title says 120–290 cm and the minimum-height spec is 120 cm. One UK review describes 30–60 cm poles. The saved listing does not resolve that clash.
What load is printed?
The bullets say 70 kg. The load-capacity line says 69.85 kg. One UK review says 90 kg. None of these is an independent test in the file.
Is a bag included, and are tools required?
The bullets include a waterproof Oxford bag and say no tools are needed. A safety lock knob is named. UK reviews say the plastic clamp slips.
Shelf prices and stars are the amazon.co.uk figures stored for this comparison on 19 and 20 October 2026. Each score is the star rating divided by five, multiplied by 70, rounded, plus a review-count band: 1–9 reviews add 5, 10–49 add 12, 50–149 add 18, and 150 or more add 25. This is not a laboratory test. Seller load lines and the word galvanised were not scored. Two products share 89. The top pick stays on the Ceta pack because that listing has 211 reviews and the FWEEK pack has 169. Best value stays on the five-piece 30–60 mm pedestal, the lowest shelf price with at least 10 reviews and a rating of at least 4.0. Thin samples, missing review text and height clashes stay in the assessment. They were not used to rewrite the scores.
Amazon stars
70%The stored figure starts with the star rating divided by five, multiplied by 70, then rounded. A 4.6 and a 5.0 are not the same starting point. The stars are amazon.co.uk's figure, not a lab score.
Review-count band
25%1–9 reviews add 5, 10–49 add 12, 50–149 add 18, and 150 or more add 25. That is why two 4.6 scores both land at 89, and why 5.0 from one review does not lead.
Badge rule
5%This does not change the number. The same score goes to the larger review sample. Best value is a different product: the lowest shelf price with at least 10 reviews and a rating of at least 4.0.
Name the job before the pack. A post end on a hard base, a joist on a slab, and a temporary third hand are three products. Measure the gap in millimetres, check the plate against the timber, and treat galvanised and a kilogram line as claims unless the listing cites a standard or a tested capacity.
A building support in this UK set is a small fitting that holds a timber post, a deck or shed joist, or a board while you fix it. The three jobs do not share one product. An elevated post base bolts down and screws to a stand-off so the end grain stays off wet concrete. A decking pedestal is a polypropylene screw foot under a joist, used on an existing hard surface. A telescopic prop is an alloy rod with pads, for holding a cabinet or a sheet while the real fixing goes in.
Steel jacks here are mostly 100–150 mm or 150–230 mm. Pedestals are 30–60 mm or 60–140 mm. A centimetre figure printed next to a millimetre title is a clash. Measure the gap, then read the title.
Ceta reviews say screws were not supplied. FWEEK reviews say the supplied screws were the wrong type for concrete. A bullet that names screws is not a resin-anchor kit.
Trade elevated bases warn against a post whose top is unrestrained, such as a fence post. These listings do not publish a capacity. Stars describe light garden frames and shed bases, not balconies.
Decide whether you need a post end on a hard base, a joist on a slab, or a temporary third hand. Measure the gap in millimetres. This set's steel jacks are mostly 100–150 mm or 150–230 mm. Pedestals are 30–60 mm or 60–140 mm. A telescopic rod is 30–59 cm, 50–115 cm, or 120–290 cm. A 75 × 75 mm top plate does not cover a 100 mm post. A pedestal head cited for about 45 mm timber will not centre a much wider joist.
Galvanised without EN ISO 1461 is an unnamed zinc or paint claim. EN ISO 1461 is batch hot-dip after fabrication. EN 10346 is coated sheet before cutting, so edges are weaker. Screws in the box are often not concrete anchors. A trade connector publishes fasteners and a characteristic capacity. These marketplace listings do not. A 4.6-star pedestal is evidence about light shed bases and garden frames in the stored reviews.
Three typical situations, each with a recommendation from this comparison.
You are raising joists on a hard surface and the gap sits in the 60–140 mm title. The Ceta pack of ten is the top pick at about £33.99, with 4.6 from 211 reviews. Set the collar, then fine-tune at the base. Reviews say screws were not in the box. The seller figure of 1662 kg/m² is not an independent test.
You want the end grain clear of a wet pad and the gap is 100–150 mm. The FWEEK four-pack is about £23.99, with 4.6 from 169 reviews and a 75 × 75 × 3 mm upper plate. A 100 mm post overhangs that plate. Reviews say the supplied screws were not concrete anchors, and no load is stated. Leave it for a free fence post.
The gap is inside the 30–60 mm title and you want the lowest shelf price that still has at least ten reviews. The five-piece pedestal pack is best value at about £10.98, with 4.6 from 12 reviews. A bullet also prints centimetre ranges. Only two UK texts are stored, and neither is a finished deck.
The top pick is the Ceta Composite Decking pedestal pack of ten at about £33.99. It scores 89, tied with the FWEEK four-pack, and the Ceta listing has 211 reviews against 169. The title height is 60–140 mm. Reviewers levelled sheds and deck joists on uneven concrete, and several say screws were not supplied. The seller line of 1662 kg/m² was not scored and is not an independent test. Best value is the five-piece 30–60 mm pedestal at about £10.98. It is the lowest shelf price with at least 10 reviews and a rating of at least 4.0, here 4.6 from 12. A bullet prints 60–140 cm and 30–60 cm beside that millimetre title, and the two stored UK texts do not describe a finished deck.
5-piece decking pedestal, 30–60 mm
Lowest shelf price in the set at about £10.98, with at least 10 reviews and a rating of at least 4.0. 4.6 from 12 reviews. The title height is 30–60 mm.
Editorial
Peter F. is the editor for DIY & tools at productscompared.co.uk. Comparisons in this category are checked against amazon.co.uk listings, review evidence and public UK sources.
Guides on what to look for, how to use a product, and common mistakes.
Public UK sources and the amazon.co.uk listings compared on this page. Shelf prices read 19 and 20 October 2026. Updated 22.10.2026.
This page contains affiliate links. If you buy through them, we may earn a commission at no extra cost to you. Links use the amazon.co.uk tag pcuk26-21. Prices, stars and review counts are the amazon.co.uk figures already stored for this set. This is not a laboratory test.
