Untitled Document
home
Newsletter #1  January 2010
Happy New Year!
A dramatic year has gone by and we at Scandinavian Homes hope you are happy in your Scanhome!
We are still building houses in spite of the recession, fewer than earlier, but still, the interest is there. Another cold winter combined with doubled energy prices will probably drive home the message of the need for good insulation to most people….
Extensions and stick-built chalets
October last we built an Atlantica 55 here in Pollnaclough for Helen and Barry O’Brien. It is an extension to their Nordica 105 from 1995. The Scandinavian Homes building materials were delivered to site and the house was stick-built by Flaherty and Goaley. The access to the back of the old house on top of a steep hill combined with extra high walls in the design made it more economical to stick-build on-site. For smaller buildings, such as our Chalet 24, it also makes sense to stick-build on site rather than using factory produced walls.
After talking to a few customers during the last few cold weeks I think a few words about cost of heating could be appropriate. All our houses should perform well in the cold weather, especially the houses with passive and super passive specification. But still, there are a few things to consider:
Utilize lights for heat gain

All exterior lights use electricity and the heat given off is a total waste! Make sure you only have low energy bulbs externally, and of a low wattage! 7W is usually enough, and do not forget to switch them off in the daytime. The interior lights all help to heat the house in the winter, so they are not so critical. Two 40W regular light-bulbs used outside and left on for 1 week will use 2 x 0.04 kWh x 24 h x 7 days = 13.44 kWh of electricity. This is the same as to use the 900W heater in the ventilation system at full blast for 15 hours.
'Energy-eater' sewage treatment plant
Another energy-eater can be the sewage treatment plant. Some of them have an air-pump that uses a steady 150 Watt to run. In the Toreeny passive house, we will install a timer for the air-pump part of the treatment system and only run it intermittently, 10minutes for every hour. If there is a pump to pump the treated water up to a percolation area it is important that this pump is powered all the time, so it is not an option to switch off the whole system from inside.
Making the most of your ventilation system
The ventilation units all works with a 85% efficiency, so if you feel cold air coming in through the supply vents, there are probably heat-losses in the ducts in the attic. For bungalows this is easily rectified by blowing in more insulation over the ducts in the attic. There should be 600mm of insulation over the highest part of the ducts! Most houses do not have this, so it could be a wise investment to get a cellulose insulation contractor to come and increase the depth of insulation. This is especially valuable for those that only have rolls of fibreglass insulation in the attic. For houses with cellulose fiber, it can still be beneficial because the insulation may have settled, especially above the ducts! An interesting observation around Christmas was that the freezing fog clogged up the air-intake grille in our house. Easily solved by removing the grille for a few weeks during the winter. There are no insects to catch in the mesh at this time of the year, so all the grille does is to reduce the airflow. For those with a combination-box this should not be of any concern.
Condensation-water dripping from the unit in cold weather is normal. It should pour into the floor-trap in the floor. In normal weather there should be very little or no condensation-water forming. If there is anyway, it can be a sign of high humidity in the house. Increase the speed of the fans a little to create a quicker air-exchange!
Wood stoves

All customers with a closed modern stove seem to be very happy with the performance. It is so easy to increase the temperature quickly if you have been away with the heat off for a few days. A stove will always leak some heat through the flue-pipe, but the amount of leakage is dependent on how airtight the stove is and how tightly the air-intake at the bottom of the stove closes. The Jydepejsen and other good modern stoves will close quite well so that even on stormy days. when the up-draft in the flue-pipe or chimney is large the air-leakage is quite small.
At the moment we have a few Jydepejsen Comfort Line stoves at a special price for €1053 - or our besteller Zeus stove in soapstone for €2335, contact us for details

What heating sources suit your Scanhome best?
The size of your house and your requirements for heat and comfort determines what the best combination of heat-sources is. The ideal might be to get the bulk of the heat from either: Stove, Air-air heat-pump or Pellets-stove - use the electric floor-heat as a complement only. The cost of using a little electric floor-heat in the tiled areas is very small provided that the general temperature of the house is provided by one of the above methods.
If you experience a room that is hard to heat, we sell a plug-in thermostat controlled micro bedroom-heater with 200W output. This can heat a bedroom for the night. The cost to run at night-rate electricity between 23.00- 07.00 is €0.15 for the 8 hours. Connect it to a socket via a timer to ensure that you only use night-rate electricity. Cost to buy is 24€. contact us for details
Air to air heat pumps
A real energy saver are our Panasonic air-air heatpumps and the ideal quick-fix for concrete houses that are difficult to heat. Also suitable for larger Scanhomes with open plan. Cost of running at night rate is unbelievably low: € 0.95 for 8 hours, while the output is up to 11.5 kWh. You can have one installed for around €2400 including VAT and installation
contact us for details


You can also visit our Heatpump webpage for more information heatpumps.scanhome.ie
All this leads me to want to write a few words to increase the understanding of energy usage and how to calculate it. 100 Watt is the usage of one old light-bulb. If this is used for 10 hours, it will use 100W x 10h = 1000Wh = 1 kWh, this is what ESB calls one unit of electricity. With the help of the list below you can figure out how much Watt (heat) is needed continuously to heat your house to 20 degrees in the coldest weather conditions. It is also assumed that the house is inhabited so that the passive heat from the habitants and their activities helps to heat the house. If the insulation and ventilation is done correctly, your house should perform like one of the following examples:
Low energy house:   <20W per m2 of floor area
For a 100m2 house, this is 20W x 100m2 = 2000Wh = 2kWh of energy per hour, over 24 h this is 48kWh of energy used, same as 48 units of electricity per day.
145mm insulation in wall
60mm insulation in foundations made before 2006
300-400mm of roof insulation in bungalows and two-storey
175mm in sloping roof for those with converted attic
Passive house: <10W per m2 of floor area.
For a 100m2 house, this is 10W x 100m2 = 1000Wh = 1kWh of energy per hour, over 24 h this is 24kWh of energy used, same as 24 units of electricity per day.
215mm insulation in wall
280mm insulation in all foundations made after 2006
600mm of roof insulation in bungalows and two-storey
400mm insulation in sloping roof for those with converted attic
Super-Passive house: <5W per m2 of floor area
For a 100m2 house, this is 5W x 100m2 = 500Wh = 0.5kWh of energy per hour, over 24 h this is 12kWh of energy used, same as 12 units of electricity per day.
335mm insulation in wall
280mm insulation in all foundations made after 2006
700mm of roof insulation in bungalows and two-storey
500mm insulation in sloping roof for those with converted attic
Cost comparison between electric heaters
So, after all that, how much does your house use? On your floor-heat plan you can see how much effect (Watt) each floor-heat cable can deliver. Over the years we have used a combination of floor-heat cables and air heaters in the ventilation system.
Temovex ventilation units have a built-in electric heater that can give off up to 900W if you set it to 30 degrees. If you set the unit to 21 degrees it will give comfortable air supply-temperatures and use very little electricity if your house is reasonably heated and the ducts are well insulated.
Max possible usage: 900W x 24h = 21600 Wh = 21.6 kWh per 24h day – total cost: € 4.0
The older Sebovex ventilation units are a little different; they were installed in the attic with a separate 1200W duct-heater controlled from a thermostat in the hall.
Max possible usage: 1200W x 24h = 28800 Wh = 28.8 kWh per 24h day – total cost: € 5.35
Electric towel-rail: 60W x 24h = 1440 Wh = 1.44 kWh per 24h day – total cost € 0.27
Micro bedroom-heater: 200W x 8h = 1600 Wh = 1.6 kWh per 8h usage – total cost € 0.15
Panasonic air-air heat-pump 5.4kW. Suppose that you use it at night-rate only: 11.00-07.00: 1200W x 8h = 9600 Wh = 9.6 kWh per 8h usage
- total cost is unbeliavable low: € 0.95
Suppose that you use it daytime only 1200W x 8h = 9600 Wh = 9.6 kWh per 8h usage
- total cost is still low: € 1.79
The beauty is that the output is up to 4.4 times the input (COP 4.4) This means that you get up to 42kWh of heat output. They work the best in +7 degree outside temperatures. They still work down to -15 degrees but at reduced efficiency.
Flat screen TV 40”:  200W x 8h  =  1600 Wh = 1.6 kWh per 8h usage – total cost € 0.30
Person at rest: 100W x 24h = 2400 Wh = 2.4 kWh per 24h in rest – total cost €  FREE
Person working: 600W x 24h = 14400 Wh = 14.4 kWh per 24h in rest – total cost €  FREE (if it is you who is doing the work!!)
Floorheat cables:
100W  thermostat control; 100W x 24h = 2400 Wh = 2.4 kWh per 24h day - total cost: € 0.45
200W  thermostat control; 200W x 24h = 4800 Wh = 4.8 kWh per 24h day - total cost  € 0.89
270W  thermostat control; 270W x 24h = 6480 Wh = 6.5 kWh per 24h day - total cost  € 1.21
500W  timer control;   500W  x 8h night = 4000 Wh =  4.0 kWh per 8h night - total cost € 0.39
700W  timer control;   700W  x 8h night = 5600 Wh =  5.6 kWh per 8h night - total cost € 0.55
1250W timer control; 1250W x 8h night = 10000 Wh = 10.0 kWh per 8h night - total cost € 0.98
2295W timer control; 2295W x 8h night = 18360 Wh = 18.4 kWh per 8h night - total cost € 1.81
2775W timer control; 2775W x 8h night = 22200 Wh = 22.2 kWh per 8h night - total cost € 2.19
3000W timer control; 3000W x 8h night = 24000 Wh = 24.0 kWh per 8h night - total cost € 2.36
3700W timer control; 3600W x 8h night = 28800 Wh = 28.8 kWh per 8h night - total cost € 2.83
The idea is that the larger cables should be use at night-rate with a timer. 

One 2775W cable uses 22.2 kWh per 8 hour period.
Cost for one kWh (unit) at night rate is 9.84 cent. 
This gives a cost of € 2.19 for 22.2 kWh of usage at night rate

If you use day-rate electricity with a weaker cable, but use the same amount of kWh (units), the cost is:
Two 200W and two 270W cables use 4.8+4.8+6.5+6.5= 22.6 kWh per 24h period
Cost for one kWh (unit) at day rate is 18.61 cent.
This gives a cost of € 4.21 per 22.6 kWh of usage at standard day-rate charge
The standing charge is higher for night-rate electricity; the yearly fee is € 181
The standing charge for the simple 24 day rate it is 139€ per year, a difference of € 42 per year.

If you don't own a Scandinavian Home yet it is not too late - visit us in Galway and place your order ASAP....

If you own an old, not passive Scandinavian home, you can engage Peter Flaherty and John Goaley to come and assess the situation and get a proposal for improvements.

The most common improvements that can be done to an old Scanhome are:

- Check function of ventilation
- Check the attic insulation
- Check insulation of ventilation ducts
- Installation of stove
- Installation of Air-air heatpump
- Installation of solar collectors for hot water

315mm insulation in a
super passive wall
The Scandinavian Homes Team wishes you a good start into the new year!!
Lars Pettersson, lars@scanhome.ie
Moycullen, Co.Galway, Ireland
Tel: 091-555 808