DIY MVHR & Part F Certificate

CitizenFloor

Hi - Getting conflicting information from two different MVHR providers.


One who provides MVHR (Only installed by the provider).
One who provides MVHR (Which I can install myself).


I have been reading "Part F", and "Installation and Commissioning of Ventilation Systems for Dwellings-Achieving Compliance with Part F 2019", but I am still unclear, primarily because of the language used i.e. "Competent Person".

If I have my MVHR designed with the help of the installer company, install it myself, and have it commissioned by the installer, can I achieve Part F compliance, and get the Part F certificate? Assuming everything is in order....

CitizenFloor

Or does it need to be installed by a registered installer for it to be Part F certified. I was under the impression that if it was designed and commissioned it should be certifiable.

listermint

CitizenFloor wrote: »

Or does it need to be installed by a registered installer for it to be Part F certified. I was under the impression that if it was designed and commissioned it should be certifiable.

This is accurate as far as I've researched.

CitizenFloor

listermint wrote: »

This is accurate as far as I've researched.

Per the provider I am working with, there is no problem with this approach, and its certifiable. I'm still a bit dubious, based on the fact that they are trying to get me to drop a few K, on their equipment. But they gave me the name of a local installer/person qualified to commission it....



I'm going to check with him before pulling the trigger. A good few people on here, seem to be certain that its okay too. I'm probably being overly paranoid.

hochnie

Did you ever get clarification on whether it needs to be installed by a certified installer for the part F?

I am looking to do similar as yourself on a refurb/new build, any chance you would pm the info on the unit you are installing?
thanks

CitizenFloor

Per the supplier yes, it can be Part F certified if commissioned by a registered installer. Per an independent registered installer he can commission it and it will be certified, even if I install it. So it seems to check out. There was a good bit of back and fourth between myself and the supplier on design. I currently have the final invoice, but haven't paid yet. Things, as you know, have gone a bit pair shaped. I'll ping you some details in relation to my set up, when I'm at a PC.

hochnie

Thanks very much for the info.
There are so many choices and loads of information out there, things being the way they are it s good to know there are others prepared to go down this route.
I am being quoted for a full system design,kit and commissioning (with me completing the install) for about 6k for a 350 sized.

1k of that is design and commissioning, I would like to see if that is typical but it seems reasonable.

The accessories outside of the unit itself are 2.6k which I was surprised by but maybe that is where they make their money?
Thanks

Calahonda52

hochnie wrote: »

Thanks very much for the info.
There are so many choices and loads of information out there, things being the way they are it s good to know there are others prepared to go down this route.
I am being quoted for a full system design,kit and commissioning (with me completing the install) for about 6k for a 350 sized.

1k of that is design and commissioning, I would like to see if that is typical but it seems reasonable.

The accessories outside of the unit itself are 2.6k which I was surprised by but maybe that is where they make their money?
Thanks

They are not accessories, in the same way as tyres on a car are not.:o

# key points

1. don't undersize the unit: an under sized unit means more fan speed and more noise.
2. Don't under size the ducting, same reasons.
3. don't skimp on the noise abatement options.
4. fit intake and extract away from the road.
5. fit the unit in a conditioned air space
6. pick a unit where the filters are easily accessed and changed and, if you think you need it, upgradable in terms of what they will stop
7. easily adjustable supply diffusers

The key thing about these units is that if you begin to hear them at 3am they will get in your head..

CitizenFloor

Calahonda52 wrote: »

They are not accessories, in the same way as tyres on a car are not.:o

# key points

1. don't undersize the unit: an under sized unit means more fan speed and more noise.
2. Don't under size the ducting, same reasons.
3. don't skimp on the noise abatement options.
4. fit intake and extract away from the road.
5. fit the unit in a conditioned air space
6. pick a unit where the filters are easily accessed and changed and, if you think you need it, upgradable in terms of what they will stop
7. easily adjustable supply diffusers

The key thing about these units is that if you begin to hear them at 3am they will get in your head..

Good information for me here too.....


1 - My unit is can basically cope with twice the volume of my house.

2 - I'm going with a radial system, 75mm, with two exhausts/feeds to certain rooms to cope with larger volumes. I am being assured it will be silent. Should I look to go up to 90mm? Its a retrofit so it would involved building out my stud walls about 15mm. From everything I have read, 75mm should be fine though. My Unit is meant to be really quiet too, and the fact that it is really oversized should help.

3 - Radial, with noise dampeners and distribution boxes near the unit.

4 - On a slight hill. The considerations I am making are to keep both intake and exhaust on the same side of my house, opposite side of the house to the prevailing wind.

5 - Was initially going in the attic (This is where the supplier design team put it), but I requested the design be moved to inside the hot press. Ill create a hatch for access.

6 - Must confirm this will be the case via proposed hatch. THANKS!
7 - I was told it was better not to get adjustable diffusers. I'm not sure why that is the case, and I just went with it. Need to research more.



The 3AM noise scenario sent a shiver down my spine!

CitizenFloor

hochnie wrote: »

Thanks very much for the info.
There are so many choices and loads of information out there, things being the way they are it s good to know there are others prepared to go down this route.
I am being quoted for a full system design,kit and commissioning (with me completing the install) for about 6k for a 350 sized.

1k of that is design and commissioning, I would like to see if that is typical but it seems reasonable.

The accessories outside of the unit itself are 2.6k which I was surprised by but maybe that is where they make their money?
Thanks

My system is costing ~€3.5K all in. System is speced for 220m2. My house is Approx 115m2. ~€150 for the design, which is taken off the total. Provided with drawings, re-drawings based on changes, questions answered etc. Sounds like you might be going very high end.

hochnie

Thanks for all this great information
I am still in the process of deciding which system to go with before I reach out for any more quotes.
I was a bit surprised by the quote given I would be doing the install.
The house will be about double the size of yours which obviously increases the capital cost, this is also further complicated by the fact it will
be quite long(circa 40m) with double height spaces in about a third of the space. It is a very old building with a modern extension(to be built).

given the length it would probably make sense to go with a branched system from the accessories side of things but I think the company I contacted possibly supply a 75mm radial system and long term radial seems to be the best option(health and cleaning)


The unit itself is the Zehnder comfoair q350 which does seem to be on the higher end of things so I will likely go with a more affordable system though as it is considerably more than we budgeted for.

Outside of the obvious disadvantage of lots of vents(this may not be a problem-all at the rear of our structure)and multiple units to install, what do you think about single room ventilation with heat exchangers? they "seem" to have decent power and efficiency spec's.

CitizenFloor

If your house is double mine. That sounds more reasonable......I wouldn't be too quick to downgrade. Better to invest in the unit now, and ducting if you are going for it, in my opinion.

Honestly, I'm not sure about other types of systems. I don't have any experience in the industry or anything....just telling you my experience. I PM'd you some info about my suppliers as another option!

CodeJACK

Im glad I found this an other threads as I was about to purchase online and install myself. It was already a stretch to afford the MVHR system so Im guessing that a requirement for design and commissioning may price me out.

CodeJACK

CitizenFloor wrote: »

If your house is double mine. That sounds more reasonable......I wouldn't be too quick to downgrade. Better to invest in the unit now, and ducting if you are going for it, in my opinion.

Honestly, I'm not sure about other types of systems. I don't have any experience in the industry or anything....just telling you my experience. I PM'd you some info about my suppliers as another option!

Any chance you could send me the same PM of contacts?


I've tried a few places now and nobody willing to deal with a DIYer