Joining flexible ducting

[richo106]

Typically I have 1 x 10m run to do to complete my MVHR first fix and have only got 2 x 6m pieces left

 

To save me buying another 50m roll could I just join them with a couple and some air tight tape?

 

Its 75mm OD and 63mm IN

 

any suggestions welcome

[richo106]

https://www.ventilationland.co.uk/product/25376/ubbink-coupling-piece-for-round-duct-o-75-63.html?utm_source=googleshoppingUK&utm_campaign=googleshopping-FeedUK&gclid=EAIaIQobChMIjZnshPO2gAMVztbtCh1HrgefEAQYAiABEgK51PD_BwE

 

would something like this be suitable?

[Kelvin]

It’s what I did using a similar type of coupler. I’ve not taped it up yet though. Job for tomorrow. 

[jfb]

Or if you have a bit of air tightness tape you could tape the 75mm together then have a bit of ducting just larger than 75mm internal and tape that over the join.

[JohnMo]

15 hours ago, jfb said:

Or if you have a bit of air tightness tape you could tape the 75mm together then have a bit of ducting just larger than 75mm internal and tape that over the join.

Why bodge, do it right, you may never be able to get to the joint easily once the house is built. The right solution costs nothing, compared to another 50m of duct.

[jfb]

14 hours ago, JohnMo said:

Why bodge, do it right, you may never be able to get to the joint easily once the house is built. The rights solution cost nothing, compared to another 50m of duct.

I generally agree with the sentiment but I’m not sure in this instance there is any practical difference in results (assuming the air tightness tape is something decent like tescon vana). It might be the op has all I suggest to hand and it is a straightforward solution. 
but as always it is up to the op to weigh up the suggestions and go from there.

[joe90]

3 minutes ago, jfb said:

I’m not sure in this instance there is any practical difference in results (assuming the air tightness tape is something decent like tescon vana).

I agree, if there is a fitting designed to join the ducts then why not use it?. It’s not like it’s high pressure gas (even if it was, there are fittings fir joining those kind of pipes). Don’t waste money, use the joiner (I would).

[Nickfromwales]

I've lost count of how many Ubbink systems I've now installed, with joints / couplers a plenty (large houses / convoluted runs / asshole builders with gas nailers damaging ducts etc) and the couplers are bombproof. Just use the coupler, no need whatsoever for the tape afaic. I've not taped any that I've installed, on the proviso that the duct is supported properly (mechanically fixed) and there is zero strain on the fitting.

16 hours ago, richo106 said:

https://www.ventilationland.co.uk/product/25376/ubbink-coupling-piece-for-round-duct-o-75-63.html?utm_source=googleshoppingUK&utm_campaign=googleshopping-FeedUK&gclid=EAIaIQobChMIjZnshPO2gAMVztbtCh1HrgefEAQYAiABEgK51PD_BwE

 

would something like this be suitable?

Crack on. ☝️👌

[crispy_wafer]

@richo106 not sure of your location, but if you are anywhere near Lincoln, I've got one of these and a couple of rubber seals I could donate. (Over ordered as per)

Connector for 75mm Blaufast MVHR Semi Rigid Radial Ducting System for Heat Recovery Ventilation (blauberg.co.uk)

[eandg]

23 hours ago, joe90 said:

I agree, if there is a fitting designed to join the ducts then why not use it?. It’s not like it’s high pressure gas (even if it was, there are fittings fir joining those kind of pipes). Don’t waste money, use the joiner (I would).

Definitely - we had the same situation and our installer said just get the coupler. It's a standard product because it does the job. 

[richo106]

1 hour ago, crispy_wafer said:

@richo106 not sure of your location, but if you are anywhere near Lincoln, I've got one of these and a couple of rubber seals I could donate. (Over ordered as per)

Connector for 75mm Blaufast MVHR Semi Rigid Radial Ducting System for Heat Recovery Ventilation (blauberg.co.uk)

Thank you @crispy_wafer I have ordered a coupler and seals which are coming today

 

Many Thanks though, much appreciated