Preserving a garden bench

[Amped]

Hi all

I have a large garden bench, think public park style, and slowly it is deteriorating, not much but it is on it's way. What should I be treating / coating it with to make it last?

At present it has several coats of Ronseal Duckback on it, the stuff you would cover a rough cut garden fence with, but it's not been doing a good enough job, the feet / legs are starting to go. I know the benches you see in public parks seem to last forever, does anyone know what the council use?

Will probably have it dipped to remove the current coatings, cost of new coatings not an issue, just want to get it right and have it last another 30 odd years if not more.

Any help or info is greatly appreciated.

 

[Amped]

Apologies, I don't know what wood it is made from.

 

[foxhole]

Dipping it will probably destroy it and all the joints

 

[Munroast]

is "Duckback" water based and would dipping it remove it ? (probably wreck the joints)

Is the wood hardwood or softwood ? take a pic of some endgrain.

probably softwood if it is rotting! and not much you can do, simplest solution to buy a hardwood bench. If saving the old one is a must, dismantle it (dipping will be a good start to weaken the joints) then get all the wood pressure treated (tanilith-e) then reassemble. keep the legs on a hard surface and it will probably last another 50 years.

 

[Diver Fred]

Allow the legs to dry out in this weather, I suggest with the feet elevated. Then stand them in a (idealy) spirit based wood preserver for a hour or so.
Obtain some 100 mm X 10mm Coach Screws, find the centre of leg foot(s) and drill a 6mm pilot hole in each foot and then insert a coach screw it the pilot hole, leave a small, 6 - 10mm, gap between the screw head and leg. Doing that will stop water creeping into the legs.
Once that is done you can refinish with a suitable coating of your choice.

 

[Deleted member 174758]

I know the benches you see in public parks seem to last forever, does anyone know what the council use?

Councils used to specify teak or similar oil-rich species, such as iroko, for outdoor furniture. The species they chose are naturally oil-rich and decay resistant, but are very expensive, so you won't often find them used in domestic garden furniture. Because of the cost and scarcity of teak many councils have gone over in the last 25 years to using recycled polyethylene planks (sometimes with steel sub-frames) to replace damaged or decayed seat parts

Will probably have it dipped to remove the current coatings, cost of new coatings not an issue, just want to get it right and have it last another 30 odd years if not more.

Dipping involves immersing the item in a bath of strong caustic soda solution. This removes most wood finishes, it also removes any natural oils from the wood (which can leave naturally oily and rot-resistant species such as teak and iroko susceptible to rot) but also strips the glues out from inside the joints, meaning that your item can actually fall apart when they lift it out of the tank. So not really what you want to do!

Far better to scrape it off (using a scraper like a Linbide or Sandvik), then sand off the remaining old finish with a belt sander and/or a random orbit sander, and finally deal with any rot before refinishing (i.e. remove any punky wood with a steel brush, treat the affected area with wood hardener, then either splice-in repair pieces or fill the gaps with a 2-pack epoxy filler, possibly coloured to either hide or make a feature of the repair)

 

[foxhole]

Should not be sitting on soil or grass or poorly draining ground. You can shorten the legs to remove rot and then sit on a removable plinth ( decking board etc) which will slow any further decay .

 

[Amped]

Councils used to specify teak or similar oil-rich species, such as iroko, for outdoor furniture. The species they chose are naturally oil-rich and decay resistant, but are very expensive, so you won't often find them used in domestic garden furniture

Interesting! That makes a lot of sense.

The bench is actually a large memorial bench, that was originally situated outside a social club, it lasted 20 odd years with whatever it was originally coated in and now another 10 or more with the Duckback stuff. So, no idea what it actually is. Looking at the rotted bits, I don't think it's a hardwood though.

 

[Amped]

Thanks for all the info on dipping. I hadn't considered the glue issue. I'll just be sanding it back I think!

I'll start to look into 'spirit based wood preserver' and 'wood hardeners', if anyone has any recommended products or brands, do let me know. I'm guessing that getting it 'pressure treated' wouldn't be cheap and it would have to come apart, so I'll put that on the back burner for now. Good to have it as a possible last resort though.

I'll be looking into some feet options for the future too. Not mad keen to have anything metal on the bottom though, as it's on stone and will make a racket or scratch the stone.

 

[Deleted member 174758]

I'm guessing that getting it 'pressure treated' wouldn't be cheap and it would have to come apart, so I'll put that on the back burner for now. Good to have it as a possible last resort though.

I'd ring round local fence manufacturers and timber merchants to find out if any of them have their own pressure treatment vessel and offer a treatment service (someone in the timber trade should know). I live north of Manchester and we have two within about 20 miles as far as I'm aware - one is a large timber merchant, the other is a fencing manufacturer who run a sawmill. They can both pressure treat complete items such as farm/estate gates, because the cylinders are about 20 feet long and 5 or 6ft in diameter. The only warning is that you'd have to work in with their schedule and that your seat would probably have to share space with a half.load of timber being treated. The process takes 1 to 3 days. Here's a description of how it's done:

How Wood is Pressure Treated | Treated Wood

How Wood is Pressure Treated

www.treatedwood.com

You may also come across someone who uses a vacuum impregnation system (often called "vac-vac"), but that tends to be more industrial timber grading firms, of which there are very few

 

[Amped]

Thete's a description of how it's done here

Interesting stuff... wondering if the bench would survive the process!

 

[Deleted member 174758]

Interesting stuff... wondering if the bench would survive the process!

If the construction method is mortise and tenon and the original main joints were either wedged or pinned, then yes, it should, because the glue isn't really holding it together. Note that neither process can really be retroactively done

 

[Munroast]

I'd ring round local fence manufacturers and timber merchants to find out if any of them have their own pressure treatment vessel and offer a treatment service (someone in the timber trade should know). I live north of Manchester and we have two within about 20 miles as far as I'm aware - one is a large timber merchant, the other is a fencing manufacturer who run a sawmill. They can both pressure treat complete items such as farm/estate gates, because the cylinders are about 20 feet long and 5 or 6ft in diameter. The only warning is that you'd have to work in with their schedule and that your seat would probably have to share space with a half.load of timber being treated. The process takes 1 to 3 days. Here's a description of how it's done:

My local sawmill (who I often used to buy from) was more than happy to stick whatever I wanted in on top of their stuff free of charge. Problem was it was only every second thursday, and if they unloaded it on a sunny day and anything on top of the heap could warp out of shape. Used to have to go up and hang around in the yard till the process was finnished and take the stuff away dripping wet (which is not allowed)

 

[Deleted member 174758]

...and take the stuff away dripping wet (which is not allowed)

I've done only a few fencing jobs (well, enough) and if it's a rush you take the timber any way you can get it. When it is soaking wet it is heavy, soaks your gloves, and seems to leave you with the smell of pizza dough in your nostrils... (which is quite pleasant, really)

 

[Amped]

So, current thinking:

Sand the whole bench back.
Don't get it dipped.
Treat the rotted bits to some wood hardener (probably the Ronseal stuff).
Give the whole thing a coat of clear wood preserver (probably Cuprinol).
Then give the whole thing a couple of coats of wood protector (probably Cuprinol again).

Does that sound like a reasonable plan? It might not be as comprehensive as getting it pressure treated, but I'm hoping it will extend it's life.