HELP ADVICE UFH REQUIREMENTS

[Adam E]

UFH  Any advice, criticism or reassurance welcome 

 

I have never had ufh or a ashp so absolutely no idea what the best options are so any advice or help would be appreciated 

 

I Got a quote from wanda for my UFH 115m2 it will be running off a 8.5kW ashp so they recommend pipe spacing of 150mm which I will be fitting myself (with a mate or two } stapled on to 150mm insulation,  I have 3 prices from them not sure if it’s different pipe or less pipe  used at 200mm spacing that makes the difference, just says wandapipe But about £400 between to cheapest and most expensive  (not sure if I should post their prices) but this is the email I received

 

 

. Thank you for providing me with the information to produce this estimate for you for our Underfloor Screed system.  There are three different options available to you for your project.  The Green system uses 150/200mm pipe centres offering our most efficient and eco-friendly system allowing you to achieve great heating results from the lowest input temperatures. This will save money on running costs and at the same time reduce your carbon footprint. The Amber and Red systems use wider pipe centres and are therefore less efficient and will require higher input temperatures to achieve the same level of heating offered by our Green system and may require supplementary heating

 

It’s our forever house so not so much an issue with price, but is one pipe easier to work with?  Pex al pex is widely recommended here but not an option with wanda

We don’t like a warm bedroom so I would be happy with 200 250mm spacing in the bedrooms but it would seldom if ever be used, but I like the idea of a warm ensuite would this need a floor sensor under the tiles ?  

 

The vaulted area is open plan kitchen dining and living room, and along with the hall,porch and cloakroom will all be set to the same temperature, So do I need so many thermostats?

 

I would like a separate stat for tv room as we will use this most often so maybe a few degrees warmer ?

 

The flooring in all these areas will be Amtico or karndean   ( I remember when it was called  linoleum ) so will that have a effect on the flow temperature ?

 

Is there any way I can reduce the manifold size to 12 ports as opposed to the 14ports specified  as it would take up less room and hopefully make installation a bit easier

 

We will have a ecodan 8.5Kw ashp and 250lit unvented cylinder bought as a package and the cylinder comes complete with pumps I am assuming that is why no pumps are included in the quote ?  

 

 I am looking for a set and forget system as much as possible with off the shelf  components to make future maintenance as straight forward as possible  (I suspect some of the members on here are in Mensa where  I could join Denser ! )  So I want to keep it simple

 

I hope this makes some sort sense I just want as much information as possible before I pay wanda for the design and material       Thanks Adam

plan 2.pdf UFH 1.pdf

[Adam E]

Information from wanda   I am out of my comfort zone with computers  Adam

[ProDave]

Go with no more than 200mm spacing.

 

It sounds like you want a zoned system so each room has it's own thermostat and can be set to your required temperature.

 

Do you have a floor pipework plan to see what they are proposing? I can't see how to comment on the number of zones without that.

 

If they are proposing a set of pipes under the hallway (right through the middle of the house) then delete that. I can say from experience it is not needed to heat an inner space like that.  That will reduce your zones a bit.

 

What are the overall insulation levels of the house? MVHR fitted or not etc?

[Adam E]

Thanks Dave  its a scotframe 4 star like sips panels tripled glazed with 150mm celotex on floor bungalow and will have mvhr

i haven't  got a plan that will come when i place the order apparently 

 

[ProDave]

I would tell them you are ready to place the order but need to make some tweaks to the design, so you need the pipe plan in advance of placing the order.

 

Definitely omit the UFH from the inner hall and perhaps just include the WC as part of the tv room loop(s)

[Adam E]

Thanks Dave I will contact them on Monday and hopefully post the pipe layout plan 

 

[Alexphd1]

I would target 150mm pipe space.

 

As I read your quote, the green, amber and red all use the same spec of pipe just different spacing and I am pretty sure wunda use pex/al/pex

 

Wunda are normal pretty good but I think you can quite easily cut down loops from 14 on 115m2 floor. Possibly the easiest way to do this is use 120m coils instead of 100/80m. 

 

Throw your plans out to other suppliers quick rough calculations is £2k for UFH material. 

[Adam E]

yes your rough calculations are almost spot on, Anyone any thoughts on the pump requirement ?   

not sure if  I would need a pump set  on the manifold or if the supplied pumps with the ASHP and cylinder package would be sufficient ? 

 Mitsubishi Eco dan 8.5Kw with 250lit  unvented cylinder