Clause 804 (UGM, or unbound granular material) is a crushed, well-graded sub-base aggregate used across Ireland beneath driveways, patios and paving foundations. It’s specified against standards like SR21 and EN 13242, and quarry-direct suppliers such as Poweraggregates supply it by the tonne bag or bulk load nationwide. If your project involves any of the following, 804 is almost certainly your material; for other specialist sands like glass sand, consider their specific uses.
- Driveway construction, tarmac or block paving
- Patio and hard landscaping foundations
- Shed and outbuilding bases
- Pathways carrying foot or light vehicle traffic
For decorative surfaces or a wearing course you’ll need something else, and we’ll cover that further down. For everything structural underneath, order by the tonne through a shop that handles bulk and bagged delivery.
Key Takeaways
Clause 804 works reliably in Irish ground conditions only when its grading meets SR21 or EN 13242 and it’s compacted in controlled lifts over a properly prepared subgrade.
| Point | Details |
|---|---|
| Match material to job | Use 804 for structural sub-base under driveways, patios and paths, not as a finished surface. |
| Demand a grading certificate | Confirm SR21 or EN 13242 compliance before accepting a bulk load. |
| Compact in lifts | Work in 150 to 300mm lifts for plant compaction, thinner for hand-operated wacker plates. |
| Order with allowances | Add 10 to 15% extra tonnage for compaction loss and wastage. |
| Buy quarry-direct | Poweraggregates supplies graded 804 by tonne bag or bulk load with nationwide delivery. |
Table of Contents
- What is 804 sub base made of?
- Where should you use 804, and where should you avoid it?
- What standards should your 804 sub base meet?
- How much 804 do you need for your project?
- How do you install 804 sub base properly?
- Buying 804 sub base in Ireland: what to check first
- What people get wrong about 804 sub base
- Order 804 sub base direct from the quarry
- Sources
- FAQ
What is 804 sub base made of?
804 stone is a crushed, angular aggregate graded from dust up to 40mm particle size, sometimes described by Irish suppliers as “dust to 40mm” material. That range matters more than most buyers realise. A well-graded mix packs the larger stones together with finer material filling the gaps, which is exactly what gives a compacted sub-base its strength.
Crushed, angular particles interlock under compaction in a way that rounded river gravel simply can’t. Rounded stone rolls against itself; angular stone locks and holds a load.
Fines content, the dust and smaller particles under 5mm, plays a dual role:
- Too little fines and the layer stays loose, with poor compaction
- Too much fines and water struggles to drain through, risking waterlogging and frost heave
Getting that balance right is precisely why gradation is treated as a controlled property in unbound granular material rather than left to chance.
Where should you use 804, and where should you avoid it?
804 sub base is the right call for driveways, patios, block paving bases, garden paths and light-traffic parking areas. It sits beneath the surface, doing the structural work nobody sees once the job is finished.
It’s the wrong call as a finished surface. 804 isn’t designed to be walked on or driven on directly, it has no aesthetic finish, and it will rut and shift under repeated wear without a proper top layer. For a decorative or wearing surface, look at gravel finishes or natural paving instead.
- Good use: structural base under tarmac, block paving, concrete or resin-bound surfaces
- Poor use: standalone driveway surface, decorative garden dressing
- Add a geotextile membrane where the subgrade is soft, clay-heavy or prone to waterlogging
Pro Tip: Lay a geotextile membrane between soft or clay subgrade and your 804 layer. It stops the sub-base migrating into the soil beneath, which is one of the most common causes of driveways sinking within a couple of years.
What standards should your 804 sub base meet?
Not every load of “804” sold in Ireland is equal, and this is where a lot of DIY driveways go wrong. Ask your supplier whether the material meets SR21 or the equivalent EN 13242 specification for unbound granular mixtures, and whether it comes with a grading certificate.
A handful of technical properties actually determine how the finished job performs:
- Fines content: the percentage passing the 0.075mm sieve, which controls drainage and frost susceptibility
- Particle shape: angular, crushed stone rather than rounded or partially crushed material
- LA abrasion value: a measure of how well the stone resists being ground down under repeated compaction and traffic
- CBR strength: for heavier-duty applications, Clause 804 material is typically specified against a CBR of 20 to 30% depending on the traffic loading expected
These aren’t abstract numbers. Poor fines control leads to standing water and frost heave over a single Irish winter. Weak particle shape means the layer never locks together properly, and it shows up as rutting under a driveway within a year or two. A supplier who can hand over a grading certificate on request is one who takes these figures seriously, not one just moving stone off a pile.
How much 804 do you need for your project?
Coverage depends on compacted depth, and depth depends on the job. A patio typically needs 50 to 100mm compacted, a domestic driveway 100 to 150mm, and anywhere carrying heavier vehicle loads should go deeper still.
- Convert your area to cubic metres: length × width × depth (in metres)
- Multiply by roughly 1.8 to 2.0 tonnes per cubic metre to estimate tonnage, since 804 compacts denser than loose gravel
- One tonne bag typically covers around 15 square metres at a shallow compacted depth of about 5cm, though coverage narrows fast as depth increases
- Add 10 to 15% extra for compaction loss and wastage, particularly on uneven ground
- For anything over 3 to 4 tonnes, bulk tipped delivery usually works out more economical than multiple tonne bags
How do you install 804 sub base properly?
Skip the preparation and no amount of 804 will save the finished surface.
- Strip and proof-roll the subgrade. Remove topsoil, roots, and any organic material, none of it belongs under a structural layer because it decomposes and creates voids later. Proof-roll with a plate compactor or roller to identify soft spots before you add anything on top.
- Set your falls and levels. Aim for a minimum fall of around 1 in 60 to 1 in 80 away from buildings so surface water has somewhere to go. Mark levels with pegs and string lines before spreading any stone.
- Place in controlled lifts. For plant compaction, work in lifts of roughly 150 to 300mm, compacting each layer fully before adding the next. Thinner lifts of around 100mm suit hand-operated wacker plates on smaller domestic jobs. Piling the full depth on in one go and compacting once is the single most common shortcut that fails.
- Condition moisture and compact. Slightly damp material compacts far better than bone-dry or saturated stone. Most specifications target something close to 95% Standard Proctor density for structural applications, though domestic jobs are rarely tested this formally.
- Check drainage and proof-roll again. Walk the finished layer looking for pumping, flex, or standing water. A free-draining but stable subbase beats an overly open, permeable one that loses structural integrity.
Pro Tip: If you’re compacting by hand, go over each lift in overlapping passes from at least two directions. A single pass in one direction leaves compaction gaps a plate compactor alone won’t catch.
Common pitfalls worth flagging: too much fines content causing waterlogging, lifts laid too thick for the compactor available, and skipping proof-rolling on soft or previously disturbed ground. Every one of these shows up as cracking, sinking or rutting within a year, not decades.
Buying 804 sub base in Ireland: what to check first
804 sub base in Ireland typically comes in three formats: bulk tipped loads for larger jobs, one-tonne bulk bags for driveways and patios, and smaller bagged quantities for tight access sites. Bulk tipping usually offers the best value per tonne but needs space for a lorry to access and drop the load.
Before you order, ask your supplier:
- For a grading certificate confirming SR21 or EN 13242 compliance
- Whether a sample is available before a bulk order
- What delivery lead times look like, and whether tipping or crane-off delivery is available
- Whether the quarry source is consistent, so repeat orders match
| What to check | Why it matters |
|---|---|
| Grading certificate | Confirms fines content and particle size meet SR21/EN 13242 |
| Delivery format | Bulk tipping suits larger jobs; tonne bags suit restricted access |
| Quarry source | Direct-quarry supply reduces variability between loads |
Buying quarry-direct, rather than through a middleman, generally means more consistent grading between loads and better traceability if a problem ever needs tracing back to source. It also tends to mean the person answering the phone actually understands what CBR and fines content mean, which matters more than it sounds when you’re ordering for a job that has to last.
What people get wrong about 804 sub base
Most guidance on sub-base material treats it as an afterthought, a box to tick before the “real” work of laying a driveway or patio surface begins. That’s backwards. The sub-base is the one layer of the job you can’t fix later without ripping everything up, so it deserves more attention than the surface finish, not less.
The conventional advice to “just get some 804” undersells how much variation exists between suppliers. Fines content, particle shape and compaction behaviour differ genuinely enough that two loads both labelled “804” can perform very differently under the same driveway. A grading certificate isn’t paperwork for its own sake, it’s the only way to know what you’re actually compacting into the ground.
If there’s one priority worth fixing first, it’s this: sort your drainage and subgrade preparation before you think about tonnage. A perfectly graded 804 laid over unprepared, waterlogged clay will still fail. Get the groundwork right, buy from a source that can prove its grading, and the rest of the job becomes straightforward rather than a gamble.
— Constantin
Order 804 sub base direct from the quarry
Poweraggregates cuts out the middleman that inflates prices and slows delivery on standard building materials. As a quarry-direct supplier based in Cork, stock moves straight from the quarry face to your site or driveway, with SR21 and EN 13242 compliant grading and nationwide delivery across Ireland.
Ordering is straightforward whichever route suits your project:
- Order tonne bags or bulk tipped loads through the online shop
- Call ahead to request a grading certificate or a sample before committing to a bulk order
- Ask about delivery lead times for larger driveway or landscaping jobs
Once your sub-base is sorted, browse the decorative stone range for the finish that goes on top, whether that’s gravel, natural paving or a bound surface. Get a quote today and have material on site within days, not weeks.
Sources
- User Guidelines for Waste and Byproduct Materials in Pavement Construction (FHWA appendix)
- 804 Paving Sub Base – 1 Ton Bag | Tile Merchant
FAQ
How much is a load of 804 in Ireland?
Prices vary by region, quantity and delivery distance, so it’s worth getting a direct quote from your supplier based on tonnage and delivery format, whether that’s bulk tipped or tonne bags.
What is 804 stone used for?
804 is a crushed, well-graded sub-base aggregate used beneath driveways, patios, block paving, paths and shed bases, providing a stable structural layer rather than a finished surface.
How much does a tonne of 804 cover?
Coverage depends on compacted depth, but as a guide, one tonne bag covers roughly 15 square metres at a shallow depth of about 5cm; deeper layers for driveways will cover proportionally less per tonne.
Can you use 804 to make concrete?
No. 804 is an unbound granular sub-base material, not a concrete aggregate; it lacks the graded fine and coarse aggregate mix and cleanliness needed for a structural concrete mix.