Heating: heat pump - commissioning/Loft: insulation 2

Having finally got electrics running in the house, it wasn't long before we'd have heating too. Richard returned a couple of days after the house went 'live' to commission the air source heat pump. He'd already completed the mechanical installation a few months ago, so this stage was primarily about making all the electrical connections and setting up the system.

Once the heat pump was hooked up outside, Richard wired up the hot water cylinder.

The heating has to be commissioned by a certified installer in order to claim back the government's Renewable Heat Incentive payments. Over 7 years, we should receive back more than the cost of the complete heating system, so it really does pay to 'go green'.

It's alive! The computerised control panel shows details about what the heating system is doing and how much electricity it's using (and saving).

Richard spent a bit of time adjusting and fine-tuning the controls; it's very much a 'fit and forget' type of system, in the sense that once it's configured, the control panel will automatically adjust itself to compensate for outside temperatures, run maintenance and defrosting programs, etc. All we need to do is choose the room temperature we want via the thermostats and the system does the rest...      

... but then we hit a snag. The thermostats all lit up around the house, but unfortunately the heating system didn't respond properly to the stats. We'd installed the manifolds and underfloor heating ourselves, so if anything was wrong with that side of the system, the heating company had no responsibility to repair it. This was all very worrying and we were racking our brains to work out what we might have done wrong...   

Luckily, further investigation revealed it wasn't us who had goofed but the electricians! They'd managed to mix up some of the wiring from the stats to the control box, but made amends by coming round to put it right the same day. At last we had heating! 

After one day the house felt lovely and warm; the underfloor system was so impressive and it felt like the whole house had finally been brought to life. But having heating was no good if it was all disappearing straight out of the roof. We had deliberately delayed putting in the insulation on one side of the loft, to allow the electricians better access when fitting the ventilation controls and downlights. Now the heating was on, we wanted to keep as much of it in the house as possible, so it was time to finish laying the insulation.

Getting to the eaves proved a tight squeeze. 

Having spent so much time getting the ceilings finished, the last thing we wanted to do was put a foot through the plasterboard, so had to be extremely careful whilst perched on short planks of wood.  

The layers of loft insulation are almost half a metre thick, so should keep things nice and warm in the rooms below.

As part of the 1st fix, Alan had installed all the ventilation ducts on 'legs' to allow them to sit above all the insulation. As well as allowing easy access to the ducts, keeping them above all the thermal insulation will help block out any additional noise from the extraction system. The extractor is designed to run constantly so we were concerned about noise, but were pleased to find that you can barely hear it standing up in the loft, never mind in the rooms below.

The first layer of thick loft roll is laid in one direction...

...and the second layer goes over it cross-ways to ensure every small gap is filled.
  

Modern building regulations specify that ventilation has to be tested and certified (yet another thing that you have no choice but to pay for... grr!) To make access slightly easier for testing and any future servicing, we made some wooden walkways that run across the length of the roof space.

We also made a central platform, so that we can use that part of the loft for additional storage.

With the ceilings fully taped and jointed, it was pitch black up in the loft and a wander lead was needed to see what we were doing. During the 1st fix, we'd asked the electricians to route an additional mains cable loop up there to use for permanent power and lighting, so it was a good time to get that sorted.

The loop of cable had just been left in a pile on the floor so the first job was to untangle it all and get it routed to where we were siting the sockets.
   

We'd discussed the plan when the electricians were last here and they were more than happy for us to do all the work ourselves. We clipped the cable neatly around the loft and Alan wired everything up to the sockets. As advised by the electricians, we also installed a 5 amp fused spur off the power circuit to use for the lighting.   

You don't want to be fumbling around in the dark looking for a light switch, so it was important to put it within direct reach of the loft ladder. To avoid drilling through any loft trusses, Alan made a little block for the switch to sit on...

... and wired it all up. One switch illuminates the 'storage' side of the loft and the other does the fully boarded side.  

Permanent lighting and power sockets installed. Low energy lighting throughout but it's certainly bright enough... 

... just need to tidy up all the mess; no excuses now we can see what we're doing!