Almost all quay heading on the Broads is timber, and almost all of that timber is one particular species. Here is what it is, where it comes from, how it is treated and why the thickness matters more than anything else.
Most people who own quay heading have never thought about what it is made of. It is a row of posts holding the garden up, and that is as far as it goes until it stops working.
It is worth a few minutes, because the material and the specification are what decide how long it lasts, and they are the part of a quote that is easiest to get wrong.
It is timber, and it is redwood
Roughly 95% of quay heading on the Broads is timber. Steel, concrete and plastic all have their place and we install all three, but timber is what the overwhelming majority of Broads properties have and what most replacements call for.
Of that timber, almost all is redwood: a softwood grown in Scandinavia. It grows relatively quickly but stays dense for the rate it grows, which is the balance you want. It is dependable, it takes treatment well, and it has been the standard on these rivers for decades.
Occasionally, when redwood is short, spruce is offered instead. It is a lighter timber and noticeably paler when it goes in, which the Broads Authority is not always keen on. Within six months everything on the river weathers to the same colour anyway.
Where it actually comes from
The timber is grown in Scandinavia, shipped across the North Sea into Great Yarmouth, and pressure treated at a mill there before it comes to us.
There is something quite satisfying about that. The wood holding up a garden at Ludham came in through the same port that has been landing timber on this coast for centuries, and it was treated a few miles down the road.
Treatment
Untreated softwood in permanent contact with wet ground does not last. Pressure treatment forces preservative deep into the timber rather than coating the outside, which is what makes it viable at all in ground and freshwater contact.
There is a British Standard for this. BS 8417 sets out how timber should be treated according to where it will end up, using the Use Classes defined in BS EN 335. For wood in permanent ground or fresh water contact, or providing exterior structural support, Use Class 4 protection must be achieved. Anything less and it will not last.
Quay heading is about as clear a Use Class 4 application as exists. It is in the ground, it is in the water, and it is holding your garden up.
The timber we use is also sustainably sourced, from managed forests rather than felled wild. That is worth knowing given where it ends up.
What to ask: what use class is the timber treated to? The Wood Protection Association's own advice to buyers is to specify the use class in writing and ask the supplier to confirm it on the delivery paperwork. There is also a third-party verification scheme, WPA Benchmark, for exactly this reason.
Thickness, and why it is the number that matters
This is the important part.
We use a two-inch pile. Some contractors quote an inch and a half. That sounds like a small difference and it is not: it takes roughly 30% off the material cost of the job.
Because the material is a large share of the total, that lets a contractor come in noticeably cheaper without giving up any margin. The customer sees a better price. What they do not see is that they are getting less timber in the ground.
Finished, the two look much the same. The difference emerges years later.
What thickness of pile, and what use class is the timber?
Both are invisible once the job is finished. Any contractor confident in their specification will answer without hesitating.
We put ours in writing on every quote.
The other materials, and when they are right
Steel. Stronger, longer-lived, more expensive. Right for commercial sites, heavier structural work and situations timber cannot handle.
Concrete and precast. Used where the job calls for a retaining structure rather than a piled edge.
Plastic. Genuinely long-lived and increasingly asked for by people who would rather not do the job again. Worth knowing that switching from timber to plastic is a change of material, so it needs planning permission even on a short run. See the permissions guide.
Alder poles. Not quay heading in the usual sense. A row of small tapered timber poles, typically 100 to 150mm across at the base, driven into the bank. The gaps between them let water voles, slow worms and small birds get through to the bank behind, so it slows erosion without creating a hard edge. Clients almost never ask for it by name. We suggest it where a hard quay heading is unlikely to be permitted, and the Authority is often much happier with it.
How long should it last?
A properly specified quay heading, put in straight with sound tie-backs, will typically give you ten to fifteen years.
That figure moves with the site. How wet it is, how exposed to boat wash, whether the capping sheds water properly, whether the tie-backs were done properly, and whether anyone keeps the weed off it all make a difference.
A thinner pile will not last as long. That is the whole argument for specifying properly in the first place. Doing this job twice means paying twice for the access, the plant, the permissions and the disruption to your garden, and the difference in material cost between the two specifications is a fraction of what it costs to do it all again.
Ask any contractor what they expect the work to last, and ask them to put it in writing.
Inspecting your existing quay heading
If you want to know what your existing quay heading is and how much life is in it, we will come and look.