Passivhaus Certification

And finally we received news over the Easter holidays, that our new self-build house has achieved Passivhaus Certification.

It is officially the first one to be built in Weymouth, and only the second so far in Dorset!

IMG_2739

Our plaque will take pride of place by the front door.

note to self

IMG_1778    IMG_1781

Self builder, please remember that all electrical elements i.e. lighting, and sockets that are out of reach need priority before the scaffolding is removed!

We have spent the last few days building a 6m tall tower in the hallway to install the central light fitting…. in hindsight this should have been done before the staircase was built and the scaffolding was removed to enable floor polishing.

IMG_1693

 

 

PH performance

img_1764  image  img_0322  img_1765

Over the last week the external temperatures in Dorset  have been ranging between -5 degrees C at night and +5 degrees C in the day time, sometimes reaching up to +8 degrees C on a sunny day.

We have noticed that the house maintains a constant temperature internally of around 20 degrees C in the rooms that face south (sometimes reaching up to 21/22 degrees C on a sunny day) and a constant 18 degrees c in the rooms facing north.

Something strange happens in the mornings when we wake up. I would expect the temperature to have dropped internally over night to correspond with the external drop in temperatures but it doesn’t.

Instead we have a warm and fresh, very comfortable feeling inside the house at 7am.

Why is this?

Is the slab heating up in the day time and acting as a heat sink releasing the heat at night?

Or is it the heat recovery unit balancing out the temperature whilst we are sleeping?

Or can the Warmcell insulation be acting as the heat sink?

Or is the timber frame detailing working hard at not allowing any cold bridging?

Or is it that we have never experienced living in an air tight timber framed house before? There is no moisture build up or cold spots on any of the internal external walls, & how are the ‘GORTEX’ vapour barrier and breather membranes performing?

Or is it a combination of all of the elements working hard together which is the Passivhaus principles?

Can someone please explain in plain English why we have a beautifully warm house ( without ANY  heating ) first thing in the morning…….

 

Moving in

IMG_0424  IMG_0540

With the completion of the oak floor upstairs and a flushing toilet we are able to move into the house.

We still have an enormous amount of work to do such as hanging internal doors, (and curtains), plumbing in bathrooms, installing a kitchen, commissioning the heat recovery unit, Passivhaus certification and signing off Building Regs………. not to mention the externals.

Jim is back on site this week to install the manhole covers.

We woke up early on Saturday morning excited to see the sun rise again over the coast path, and watch the many flocks of Canadian geese in perfect flight formation readying for their lengthy migration. It is so beautiful and mesmerising looking out of the window and watching the boats coming out of the harbour. The children have been occupied finding their old toys. Was it really 18 months ago we moved out? It feels like much more….

img_1662  img_1666

The simple things in life………….Our views are back too 🙂

 

 

 

Heat Recovery

Today the heat recovery unit is being installed.

It is a PAUL NOVUS 300. It will bring fresh air into each room in the house via the ducts, whilst extracting the stale moist air. The unit cleverly extracts the heat from the stale air and puts it back into the building with the incoming fresh air. There are filters inside the unit which will provide clean, pollen free air. ( We can also open the windows if we want some wind to blow through, or listen to the church bells!)

IMG_0537   IMG_0541   IMG_0539

These photos were taken on site in July last year when the timber frame was being constructed. The duct work for the heat recovery runs in the first floor void from the plant room. There is an intake and extract duct for each room.

It is crucial that the services are coordinated with the structure at the design stage.

image   image

The staircase

Whilst the roads were quiet yesterday I took the opportunity to visit Asaf’s workshop to see the staircase in production.

image

We spent along time sketching and designing the staircase, and to finally see and smell(!) the Oak treads and risers machined and assembled so beautifully was a real treat.

It will hopefully be installed after the floor has been polished.

Dry lining and shadow gaps

It feels as though we have been tacking plaster board for weeks…

image  image  IMG_1295

The main difficulty has been specifying and fixing the shadow gap beading to skirting, architraves and the edge bead to top of walls.

We have designed a gap in the plaster board between the top of walls and sloping ceilings where the LED strip lights are concealed. A 45 degree angled batten has been fixed behind the board which the LED strip will sit and hopefully direct light up into the apex of each ceiling in all the bedrooms.

We found a great product online from Renderplas which creates the shadow gap for each application and is available for both 12.5 & 15mm board sizes.

The vast amount of skimming has begun, and it’s all hands on deck preparing and decorating ready for the concrete floor polishing on the 6th of July.

IMG_1338

 

Meanwhile Internally

image

Our joiner, Asaf Tolkovsky has made a 1:1 model of the staircase. He will be able to cut all the pieces as a kit of parts on his CNC machine in his workshop, and then assemble them on site. It’s following the same philosophy as the house, where the whole structure was pre-cut in the factory and brought to site.

Another air test – 0.37ACH

After a full on week filling the narrowest of gaps underneath all the external door thresholds with silicon, more taping and more filling (the edge where the concrete slab meets the threshold), today we had our second air test.

Calculating internal volumes of the house is pretty complex. Thanks to our Passivhaus consultant Rod, who carefully calculated the whole house volume to be 613.47 m3. Our air test result achieved 0.37 ACH.

This now means we can say with more confidence that we are hoping to achieve the certified Passivhaus standards.

IMG_1220  Scan 3

Warmcel Insulation

image   image
7,680 kilos of Warmcel cellulose fibre insulation (recycled newspaper) is being pumped under pressure into the external walls and roof of the house this week.

image image image

Warmcel is insulation for timber framed buildings. The manufacturer states that ” Sustainably manufactured Warmcel provides superior performance that offers industry-leading thermal performance, ensuring your building’s U-values don’t just meet baseline building regulations, but go on to exceed them.
Warmcel cellulose fibre has a high specific heat capacity and high insulation value offering any home significant thermal mass and excellent heat retention. A Warmcel insulated home is designed to hold heat for a long time and to minimise daily temperature fluctuation- an essential quality for a comfortable environment.”