• We invite you to join UKWorkshop.
    Members can turn off viewing Ads!

Timber in Water

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

SteveW1000

Established Member
Joined
4 Oct 2011
Messages
97
Reaction score
0
Location
Leytonstone, London
Hi as a mainly lurker I'm seeking your advice. A friend is working with a school to build a wildlife garden and they want to build a jetty at the edge of their pond. The current plans are to have some posts going down in the water to support the end, apart from elm what other wood would be suitable? As money's tight we'll probably be tapping up the borough tree surgeons for some green timber.

Steve
 

TheTiddles

Established Member
Joined
14 Oct 2007
Messages
2,560
Reaction score
530
Location
Wiltshire
Scaffolding poles can be hidden and are tough enough to bang into the mud very deep to make a robust base

Aidan
 

CHJ

Established Member
Joined
31 Dec 2004
Messages
20,130
Reaction score
73
Location
Cotswolds UK
Elm is OK if permanently below water but will not do well at water air interface where it will be regularly changing between wet and dry. (Elm is used for Lock sills for instance where they are permanently immersed.)
Oak would be better for support timbers, doesn't mind wet/dry cycle. (Used for Lock gates for instance.)
 

AndyT

Established Member
Joined
24 Jul 2007
Messages
12,027
Reaction score
495
Location
Bristol
Do make sure that there isn't a rubber pond liner keeping the water in before anyone starts hammering poles into the bottom!
 

SteveW1000

Established Member
Joined
4 Oct 2011
Messages
97
Reaction score
0
Location
Leytonstone, London
Thanks for the advice, knew that Elm was used in locks but didn't know that it had to be kept wet. Can't easily use scaffold poles as it's got a Butyl Liner. Will see what the tree surgeons can find.

Got an interesting freebie coming up, a pair of replacement Oak Gates for a Grade 2 listed church. The boroughs conservation officer is going to order up the oak for the job. Needs to be an exact replacement and they've unusual wedged and pegged mortices will post up a WIP once the Oaks ordered.

Steve
 

CHJ

Established Member
Joined
31 Dec 2004
Messages
20,130
Reaction score
73
Location
Cotswolds UK
SteveW1000":1t35qnh3 said:
..... Can't easily use scaffold poles as it's got a Butyl Liner. Will see what the tree surgeons can find.
...
Square section 25Ltr Plastic drums make good floats for water edge support, even if water level drops they rest on the bottom without causing damage.
 

RogerP

Established Member
Joined
7 Jan 2011
Messages
3,785
Reaction score
2
Location
Gloucester
Greenheart (Lauraceae Ocotea rodiaei) is about the best for durability but where you could get it, what it would cost and whether it's FSC certified is another matter.
 

marcros

Established Member
Joined
11 Feb 2011
Messages
11,276
Reaction score
720
Location
Leeds
unlikely from the local tree surgeon...

If you cannot use scaffold poles because of the liner, is any form of post, whether timber or other, not going to present the same problem?
 

Jacob

Pint of bass, porkpie, and packet of crisps please
Joined
7 Jul 2010
Messages
18,967
Reaction score
1,034
Location
Derbyshire
marcros":1zts518m said:
unlikely from the local tree surgeon...

If you cannot use scaffold poles because of the liner, is any form of post, whether timber or other, not going to present the same problem?
Alder is traditional and is quite likely to be available if there are any rivers in your vicinity, though it may take a bit of tracking down.
 

woodbloke

Established Member
Joined
13 Apr 2006
Messages
11,770
Reaction score
0
Location
Salisbury, UK
RogerP":2wtnokso said:
Greenheart (Lauraceae Ocotea rodiaei) is about the best for durability but where you could get it, what it would cost and whether it's FSC certified is another matter.
I agree, if you can get hold of some gash gh (from an old dock say) then the stuff is practically nuke proof, but it's hellishly hard and the splinters are toxic. I used a bit for the bottom of a plane and it's almost as difficult as lignum to use - Rob
 

wills-mill

Established Member
Joined
29 Jan 2008
Messages
121
Reaction score
0
Location
Billingshurst, West Sussex
Alder and Beech are (like Elm) only pretty sensible when fully immersed. Sadly they'll crumble at the water level in a couple of years where the timber is constantly damp. Oak and Sweet Chestnut would be favourites, if you're pestering tree surgeons try Robinia pseudoacacia (Black Locust in the USA, Robinia over here) which is a dense and durable favourite, otherwise have a crack at lengths from conifer hedges- Thuja, Lawson's Cypress (Port Orford Cedar (USA)), or Leylandii are all very under rated.
 
Top