Finishing the roof and putting in the doors sealed the house envelope. With the weather no longer getting inside, the crew moved onto interior work such as installing the glasswool insulation and plasterboard.
Keeping the inside dry eliminated one of our regular chores. No more visits required to mop up the puddles on the floor.
Glasswool insulation goes into walls and ceiling.
An important feature of passive heating and cooling design is keeping the heat inside during winter and outside during summer. Insulation is the key to achieving this goal.
There are many different styles of insulation so it can be difficult to decide which one is right for a particular house design and location. The Alternative Technology Association is a terrific source of advice with their 2017 insulation buyers guide.
We decided to use glass wool insulation. The wall batts have an R rating of 2.5 while the ceiling batts are rated at 6.5. R rating is simply a measure of how well the insulation does its job. The higher the number, the harder it is for heat to pass through the material which means it’s a better insulator.
Wall insulation went in first.
Once the roof was finished, the crew quickly moved onto installing glasswool insulation in the ceiling.
The plasterboard was then added to seal everything in place.
In the main bathroom, adding the plasterboard helps to make the Timbercrete wall a feature of the room.
Correctly installing insulation is critical.
Just whack in some insulation and she’ll be right! Sounds simple but, like most things in life, there’s more to it than meets the eye.
Correct installation is essential for achieving the design R rating on the insulation.
Start by checking for gaps. Gaps between batts or at the edges of the cavity have a dramatic effect on performance. The effective R value drops by 50% if there are gaps adding up to 5% of the total insulated area. The moral of this story is clear. With gaps, you pay for a premium, high R rating insulation which actually performs like cheap low R alternatives.
Another item worth checking is the batts aren’t compressed to fit into the available space. Compressing any bulky material like glasswool insulation reduces the effectiveness as it relies on air pockets to achieve the desired thermal resistance.
Given the emphasis on a quality job, David inspected the wall and ceiling insulation after the installers finished. He spotted a few issues, including gaps, which meant they had to come back for a second attempt to meet his exacting standards. There’s no easy way to go back once the plasterboard is in place, so it’s essential to get the insulation right beforehand.
Floorboards in place.
Installing the recycled timber floorboards in the bedrooms was another interior job. The boards are from a demolished 1920’s tramway depot and were safely stored in the garage for the last couple of years.
We are looking forward to seeing the floorboards restored to their original splendour after sanding and polishing.
Front entrance way is coming together.
The key features of the front entrance are now in place.
Putting a curved timber wall between the Timbercrete garage walls and plain charcoal cladding highlights the entrance.
The front door itself is a work of art. David and his team lovingly restored timbers recovered from the original house on the property and reassembled them into a door.
From the inside, the transition from family living space to air lock to front door is becoming evident.
Work continues apace.
I’ll have more to report on soon. The painter and tiler arrived last week so it’s a hive of activity inside the house.