Do building standards apply?

akira181

I'm currently in dispute with a builder regarding an installation of a kitchen extract duct. They've basically cut the rigid PVC pipe too short, used around 6ft of flex ducting, and is completely uninsulated/no condensate drain fitted. The flex ducting is compressed, unsupported, loops/sags on itself, and is joined with duct tape only.
When I contested that out of the ~22 guidelines for flexible and rigid ducting stated in Scotland's "Building Standards Technical Handbook 2023: Domestic", 10 are not applicable, 10 are in non-compliance, and at best 2 are compliant.
They justified the 6ft of unsupported, compressed, sagging flex by saying "our roofers are in attics every day and they see these flexible pipes some of them being more than 6ft long".
They justified cutting the PVC pipe too short by claiming "We originally ordered the rigid pipe to do this job but when applied we found it was too heavy due to the length and it would have put too much pressure on the macflash and possibly pulled it through the roof the roofers decided to use the flexi pipe"
I don't think what other people have installed is relevant as (correct me if I'm wrong) following Building Standards is a legal requirement, not optional based on what others have got. 2 wrongs don't make a right.
Also, is macflash supposed to be used as a vertical duct support? I thought it was for weather sealing only. Either way, I imagine supporting a vertical duct at only the macflash will eventually lead to premature failing of the weather sealing.
Can someone tell me if they're just BS-ing me or am I interpreting the Building Standards too strictly? Or are Building Standards just a recommendation and don't need to be followed at all as the work doesn't require a building warant?

FreeBear

akira181 said: Can someone tell me if they're just BS-ing me or am I interpreting the Building Standards too strictly? Or are Building Standards just a recommendation and don't need to be followed at all as the work doesn't require a building warant?

Can't comment on Scottish regs or macflash. However, common sense says that flexi ducting reduces airflow and generates noise due to the turbulence created. Fan manufacturers recommend using smooth rigid ducting for a reason. All ducting, rigid or flexible, requires adequate support. If the builder is unable to fit suitable support, I'd be questioning his competence.

I would say that his excuse of the rigid ducting putting too much stress on the macflash because of the weight is BS - He should be providing adequate support at regular intervals - If this means using hangers or fixing vertical supports, then that is what should be done. And rigid ducting isn't that heavy, so no real excuse in my opinion.

weeg

Yes, even if you don't need a warrant the work needs to comply with the standards. ( I live and work in Scotland as an engineer)

akira181

thanks for the reply. What' I'm struggling with is what is a "guideline" and what is a legal "requirement"? 

For example, I've copied in what the building standards say about ductwork that I think applies to this job and how the work doesn't comply. The use of the words "General Recommendations" and "should" (opposed to must/shall) insinuates it's a guideline and they don't need to comply?

Building standards technical handbook June 2023: domestic

3.A.8 Ventilation Ductwork 

General Recommendations

Ducting should be:

• routed in a manner which minimises overall duct length and the number of bends required. It is particularly important to minimise bends in main ducts operating at higher air velocities. (flex duct loops back on itself)

• insulated where it passes through unheated areas with the equivalent of at least 25 mm of a material with a thermal conductivity of not more than 0.04 W/mK. This reduces the risk of condensation occurring within the duct (duct goes via a cold loft space. Totally un-insulated duct although I would be fine with just a condenstate trap if they actually bothered to fit one)

• insulated or be fitted with a condensate trap where a duct extends above roof level. The condensate trap should be fitted just below roof level (no condensate trap)

• fitted with a condensate trap where it is installed vertically. The trap should prevent condensation flowing down the duct and potentially damaging a mechanical extract fan (no condensate trap)

• arranged to slope slightly downwards away from the fan unit, to prevent backflow of any moisture into the unit, when installed horizontally (loops and sags all over the place)

Flexible ducting

• Rigid ducts should be used wherever possible. Where flexible ductwork is installed, this should only be used for final connections and duct lengths should be kept to a minimum. All flexible ductwork should meet the standards of BSRIA BG 43/2013. (the flex is around 6ft long)

• Ducting should be pulled taut to ensure that the full internal diameter is obtained and flow resistance minimised. This is considered to have been achieved if the duct is extended to 90% of its maximum length (flex is largely compressed)

• Flexible ducting should be supported at suitable intervals to minimise sagging. Refer to manufacturer’s information but generally it should be supported at no greater than 600 mm intervals (flex isn't supported)

• Bends in ducts should have a minimum inside radius equal to the diameter of the duct. If tighter bends are required, rigid bends should be used. (Flex does a tight hairpin bend on itself)

Duct Connections/Terminals

• Connection of lengths of flexible duct must use a rigid connector and jubilee clips or similar to ensure a long term seal is achieved. Connections of lengths of flexible duct should not be taped only. (used duct tape only)

• Connection of components should not result in significant air flow resistance. Components should be proprietary and fit easily together without distortion. (the flex is nothing but resistance and distortion)

I've also spoken with Consumer Advice and they reported the builder to Trading Standards. They said that my options were to request a discount (the builder has refused on multiple occasions) or take them to a small claims court. 

The complete bill is around £400 but the small claims process costs £110 to start. So it would be a bigger waste of my time and money than this already is. 

I feel like I have no other choice than to pay these cowboys and then pay someone else to rip out their mess and start again. Absolutely sucks

ThisIsWeird

How much would it cost to have someone else sort/redo the work correctly - eg either replace the flexi with suspended/supported rigid, or to add a support panel of some sort under the flexi?

Discount that from their £400 bill, and pay them for the rest. Then they'd have to do the chasing - and they'd struggle given the evidence you have.

akira181

If it's up to me, I would get their entire mess ripped out, the duct replaced with one of sufficient length, and flex for the final connection only, to minimise unnecessary pipe joints, and clear up all the rubbish they left behind. That would probably leave them owing me monies.

However, I'm quite positive I cannot dictate what I am willing to pay and discount their invoice as I, or any other contractor, sees fit. They've done the work and sent a bill. They refuse to admit their work is sloppy. The only real option if they refuse to accept fault or compromise is to take them to a small claims court as far as I can tell.

If I refuse to pay or just discount their invoice on my own accord, I believe they can pass the debt onto a debt collector (I got a mortgage and credit history to worry about) or worse, turn up while I'm at work and just remove what they installed. I wouldn't be opposed to undoing their work but they're likely to do more damage in the process and my partner works from home, so I don't want her feeling intimidated by rogue traders in her own home.

mexican_dave

Unsure about Scottish Law, but reckon ThisIsWeird is correct, deduct the cost to put this work right from the builders invoice. Send a covering letter with your cheque explaining the deductions and send Recorded Delivery - so you know they have had it. They would have to take you to court to get the rest of the money, which will cost them to apply, and doubt they would win as the work is contrary to "good practice" eg Building Regs. A debt collector can't collect without a court order, and if they harass you then that's a crime! Reckon only a bailiff serving the court can force entry. Be strong tough it out! Odds are the builders will not bother, just keep your letter to the facts (and keep a copy).

akira181

Consumer Advice didn't present that as an option to me. They said I couldn't discount the bill myself and pay what I felt was right, although they never said anything about getting another builder to fix it and discount that way. I'm not sure how debt collectors work but it's more the mark on my credit history I'm worried about rather than being harassed by them.

They also wouldn't have to force entry to remove anything, access to the loft is via a communal hatch in the stairwell. They have the code for the lock and they're also one of the preferred roofing contractors for the factor (clearing gutters, replacing tiles, repairing leaks, etc). They technically still own the materials if it's not paid for no?

mexican_dave

I think we need to be clear about paying a fair amount for the work correctly executed, I think using the word "discounting" is misleading. I don't think Citizens Advice is correct. You could go to the trouble of appointing a professional building surveyor to list and cost the remedial work required, use that to decide how much to pay the builders OR take the cheaper route of getting a qualified electrician or ventilation engineer to quote for the remedial work and use that.
By "factor" do you mean "landlord", if so escalate this issue to them, to warn about shoddy workmanship and let them know you will hold them responsible for any illegal entry to take back duct materials in the common space however that is accessed.
Unsure about Scottish Law, but under English Law loose materials eg a box of tiles, a bag of cement, a bundle of timber etc, can be removed if access is given by you, BUT once something is attached to the property it becomes part of the property and it is illegal in Civil Law to remove, but if that happened there is an arguement to say its theft, so a police matter.
Suggest you go back to Citizens Advice and see what they say about this again, including the issue of potential damage to credit history, not my subject.

akira181

mexican_dave said:

I think we need to be clear about paying a fair amount for the work correctly executed, I think using the word "discounting" is misleading. I don't think Citizens Advice is correct. You could go to the trouble of appointing a professional building surveyor to list and cost the remedial work required, use that to decide how much to pay the builders OR take the cheaper route of getting a qualified electrician or ventilation engineer to quote for the remedial work and use that.
By "factor" do you mean "landlord", if so escalate this issue to them, to warn about shoddy workmanship and let them know you will hold them responsible for any illegal entry to take back duct materials in the common space however that is accessed.
Unsure about Scottish Law, but under English Law loose materials eg a box of tiles, a bag of cement, a bundle of timber etc, can be removed if access is given by you, BUT once something is attached to the property it becomes part of the property and it is illegal in Civil Law to remove, but if that happened there is an arguement to say its theft, so a police matter.
Suggest you go back to Citizens Advice and see what they say about this again, including the issue of potential damage to credit history, not my subject.

A factor is a company that takes responsibility for communal maintenance of the building and charges every dwelling within a monthly fee plus their portion of any communal works (after a healthy markup). If your building has one, you have to pay them, even if they're useless and you don't want to (quite a lot are). They were the ones that recommended this builder to me however, as the work was private, they're not getting involved.

If I get a surveyor in, the surveyor alone will cost more than what it would for me to rip out the mess and fix it myself. If I get another builder in to quote to fix it, all they're going to do is provide a quote with what they're going to do. Not explain in any detail why they're doing it or highlight issues with the current install.

I've called Consumer Advice and both times they've said I cannot deduct the bill myself. Which makes sense, otherwise anyone could just get another builder in after any works to quote to "fix" something and reduce the invoice.

The real issue here is that the work was not completed as agreed, what has been done is not fit for purpose, and when it's been brought to their attention, it's nothing but excuses that don't even make sense. It's looking like a small claims court is the only real option left here

mexican_dave

Let the builders take you to court if they think they are owed money and use the quotes/surveys etc be your defence. Regarding quotes it's quite possible to ask the fellow quoting for the remedials to word report his/her quote, say for instance: "existing flexible duct unsupported in attic contrary to good practice, removal of said duct; replacing with rigid duct, etc (more words) all to comply with Building Regs." That way you have a mini report and quote in one.
Still reckon you should pay an amount you are happy to pay for work correctly executed, and see if builders chase the rest, but then I know nothing about Scottish Law!