Oil Tank Installation

[edenbridge]

I wasn't sure whether to put this under "Building", but I figured I'd find more Oftec types here than over there.

I have myself a Harlequin HZA1400 tank, and have a concrete base measuring 2400mm x 1700mm. It has 250-300mm of hardcore and a 100mm concrete topping.

However, the tank needs to be raised on piers, and I've had varying advice from my builder and a local builder's merchant:

Builder: Build the piers from 200 no-frog bricks, simply stack without using mortar, cap with two 900x600x50 slabs, then place the tank on top.
Fair enough, I could do that myself!

So I rang around for the best price on bricks, only to be told:
Use hollow blocks laid on their sides, and fill the voids with concrete, and cap with THREE 900x600x50 slabs.

However, I've found the Oftec guidelines for oil tank installation and it says to build the piers with mortar, and cap with reinforced lintels.

What is acceptable? Can blocks be used instead of bricks?

I know the easy answer is "go by the rules" but I'd like to be sure of my facts before I tell my well-respected builder that his approach may not be correct.

Thanks in advance for your help.

 

[gasandoilman]

Installing a tank is notifiable to building regs and should be installed by oftec reg engineer on the oftec site it will tell you of a nearby company.

Have you checked if it needs to be bunded?

If you do fit yourself fit to oftec standard as if not may cause problems later
Dont just put on piers as your builder said as this is a cause of tanks splitting

 

[AlanE]

Why do you need to raise it and by how much?

 

[holty]

is it vapourising or pressure jet you have.if your installing a tank these will be simple questions.if pressure jet why raise the tank, instead fit a tiger loop, but this also will require an oftec engineer.

 

[cider]

use which ever method is most cost affective providing the top of the base is supporting the bottom of the tank over its entire surface. In other words if you need to raise the tank by just 12 inches dry lay 3 layers of blocks on there sides. If however you need to raise the tank by 2 feet build 2 columns and cap with concrete lintels as OFTEC describe.

 

[Mike2007]

Well farmers seem to have them perched on top of anything thats a bit higher than their boiler (could be pallets)! Single skinned and leaking only a little.
Surely all of us can adopt such disregard for the general environment as well?

 

[oilman]

Installing a tank is notifiable to building regs

Correct.

and should be installed by oftec reg engineer

Not necessarily.

It's a pity you're using a plastic tank, steel are so much better, and cheaper. Their only disadvantage is the weight, but then tanks don't moved about much.

 

[Norcon]

Would be surprised if the steel tank is cheaper given the price hikes in steel prices recently.

 

[edenbridge]

Thanks for the responses, guys.

I won't 'quote and respond' to each of your comments, but the situation is this:
- My Oftec installer has recommended raising the tank by 500-600mm.
- He's not recommended the Tigerloop as it adds more complexity and puts more gizmos and pipes outside the house (and the boiler's on the front wall)
- He's currently on holiday for two weeks and can't be contacted!

Before he left he said to get some piers built, and that's when I contacted my builder. But I don't want any surprises for my boiler fitter when he returns, so I want to get it right.

Thinking about the "3-slab method", I'm guessing the piers need to run along the length of the tank as shown below?

I can see how slabs would be cheaper than the reinforced lintels, but it's looking like I'll need double the bricks/blocks to acheive this.

I guess I need to weigh-up the difference in cost (and labour) for laying double the bricks. I can see now why the "lintel method" recommended by Oftec is deemed the optimium solution.

Thanks again.[/img]

 

[Kes]

I'm totally bemused by the three slab method, and indeed both of the diagrams. The tank platform should be at least large enough to support the entire base of the tank, which is going to be very hard to do with three 900 x 600 slabs. (Your tank is 1803 x 1118 mm.)

We had a raised tank installed last year, on a concrete base with concrete block piers, laid flat and fcemented, with four reinforced lintels, and a slab platform on top. The platform has approx 300 mm overhang all round, the base more. The platform overhang is very handy for maintenance and simply filling the tank.

PS Yes, Oftec reg installer and certificate.

 

[edenbridge]

I'm totally bemused by the three slab method, and indeed both of the diagrams. The tank platform should be at least large enough to support the entire base of the tank, which is going to be very hard to do with three 900 x 600 slabs. (Your tank is 1803 x 1118 mm.)

I have to say I'm less convinced by the 3 slab method the more i think about it, but I'm happy that a 1800x900 platform is OK, as the tank tapers down to about 1780x840 at the bottom.

1803x1118 is the overall size to the bulbous bits, which is what the green 'tank outline' is meant to represent.

 

[Kes]

Ah, I see what you mean, the slabs will go sideways on. I should still advise a fourth slab at the business end so that the poor delivery driver has something to stand on. An overhang also protects the valve, filter and pipework that stick out at the pointy end, as indeed a larger platform tends to protect the whole tank from inadvertent bashings.

 

[gremlin16]

edenbridge

Pleased to see that you have used the OFTEC site for information regarding correct method for tank installation.

Has your installer completed a TI/133D – Domestic Oil Storage Tank Spillage and Fire Risk Assessment.

The risk assessment will determine whether you need a bunded tank. The fire risk assessment is also covered TI/133D.

He's not recommended the Tigerloop as it adds more complexity and puts more gizmos and pipes outside the house (and the boiler's on the front wall)

Honestly cant see why he says its more complex?

When we install oil lines they comprise an isolator valve, filter, fire valve
and when needed a Tigerloop.
If you don't want a Tigerloop on the outside wall, then you can get a de airator fitted internally. (a standard Tigerloop can not be fitted internally)

Cost wise, fitting a Tigerloop will be a lot cheaper than rising tank by 600mm.

 

[oilman]

Would be surprised if the steel tank is cheaper given the price hikes in steel prices recently.

You haven't seen the price hike for oil then?

 

[simond]

Clearly there is no point raising the tank unless you have an old oil AGA or similar.

A tiger loop works fine for everyone else (subject to the height of the boiler versus the tank).

The concrete slab idea is rubbish as the slabs have no tensile strength. The lintels are a must if you are using a plastic tank.

The OFTEC rules allow for the inspection of the tank in the size of the base slab. I trust you have also checked wooden fences, large overhanging tree branches etc.

If you have any airgun toting kids in the area, a steel tank may be a good idea, but bunded ones are VERY heavy if your risk assessment deems bunded is required.