April 15, 2007 by Jeff.

Let’s continue prying into this big old house.  We’re trying to reduce that $500/month gas bill and discuss what’s causing it.  Could it be those big drafty holes called windows?

As with many older houses, these windows are double-hung single pane.  Double-hung means there are two sliding sashes (the moveable parts) – an upper and a lower.  Casement windows are different – they are single sashes hinged on the top, side or bottom and typically operate with a crank.  We’ll leave those for another day.  Single pane means just that – no insulating double panes here.

There are many things we can do to make these windows more energy-efficient.  We start by making sure the putty is in good condition, replace missing sections and seal the glass to the putty with a good coat of exterior paint.

Older windows often use sash cords and weights to counterbalance them and make them easier to open.  The pulley openings let in outside air, and the weight pockets on either side of the window don’t help.  Pullman Manufacturing makes replacements featuring spring-loaded bands instead of ropes and weights.  These units seal the pulley hole and allow stuffing the weight pockets with insulation.  Highly recommended.  Tom Silva on This Old House swears by them, and so do I.  www.pullmanbalances.com 

There are fixed sash picture windows here and there.  Since these don’t operate, we make sure all seams are well caulked and painted, inside and out.  Then we buy some shrink-wrap storm window kits, the kind that mount with tape to the interior window frame.  It shrinks tight when heated with a blow drier and doesn’t look too ugly.  This extra air space adds an insulating cushion to the window, reduces condensation (condensation = rot!) and helps keep out some noise.

I’d like to shrink-wrap all the windows in the house, but we only do picture windows and operable windows in unused rooms.  We trade energy efficiency for the safety of easy exit in the occupied rooms.  Those sashes get sealed around the edges with Mortite – long claylike strips which offer a good temporary seal and won’t get in the way in an emergency.  If you can’t find it locally, these guys have it and lots of other usefull stuff:  www.energyfederation.org  

You may remember that his house has old triple-track storm windows too.  These never seal very well, but reduce wind pressure and protect the inner windows.  We make a quick check to verify that all the storm sashes are clicked in to their tracks and locked tightly where they should be.  You’d be amazed how many are down an inch or two, making them next to useless.

Barring complete replacement, these windows are now as energy efficiency as we can make them.  Next time we’ll move to the attic.  It has zero insulation, which is probably why the house structure is in such good shape.  Confused?  Stay tuned.   

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April 6, 2007 by Jeff.

A little background on my father-in-law’s house: It’s a typical 1880’s wood frame, 3 story city house – narrow and deep, wood sided, slate and tin roofed. With 6 bedrooms, 3 bathrooms, parlor, living room, dining room, back wing and various closed-in porches, it’s a prime example of too much house for modern times. Be that as it may, we need to keep it comfortable without breaking the bank. Oh – and did I mention the complete lack of insulation?

Last time I talked about managing heat production. We’re adding a setback thermostat. We turned off the radiators and closed the doors of unused upstairs rooms. I would normally recommend adding zoned heat. He currently has one heating zone – one long loop of pipe servicing all the radiators. If he could put up with the mess and disruption, I would advise him to add 2 more zones – splitting the downstairs living and sleeping areas into daytime and nighttime zones and adding a separate zone for the 2^nd floor. Each zone would have its own thermostat. Figure 15% less on that monthly $500 heating bill.

The mantra for heat is “if you don’t lose it you don’t need to buy it”. Air changes (outside air coming in) account for most of the heat loss in older houses – some are so badly sealed that their air exchange rate (how many times the inside air volume is replaced by outside, unheated air) can exceed 20 per hour. So step-2 of the long-term plan is to do a thorough job sealing up the house.

Remember the air conditioner in the window? That’s one big hole to the outside. We need to take it out. Then it’s time to close and latch all the storm windows. Although double hung aluminum storms are not great, they are better than nothing and at least keep wind pressure away from the windows.  There are quite a few hanging open a bit, or just not closed at all.

Old double-hung windows suffer from a multitude of ills. We’ll discuss them in a future post. For now, let’s just say that we use weatherseal tape (plastic tape that doesn’t harm paint) to seal all the windows on the second floor and the tops of the first floor windows. Why don’t we seal the bottoms? We want them to open easily in case of fire. No one is living upstairs, so we can seal those windows completely.

It’s an old house. Lots of doors, none of them well sealed. My preference is to install insulated fiberglass doors, but that’s a job for warmer weather. So for now we add foam weatherstrip to the outside doors and make sure the storm doors latch properly.

Let’s move outside. Hose faucets and other wall perforations get caulked or filled with expanding foam, depending on their size and location. Keep in mind that sunlight destroys the foam, so don’t use it in exposed areas – it will get brittle and fall apart. Window casing gets caulked both at the wall and where the storm window frame hits it. We never, ever caulk the bottom of the storm window frame – it needs to be left open to let rain seep out. While we’re at it, we clean the seep holes to make sure water doesn’t build up and rot the wood.

Next time: What do to about old windows…

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April 1, 2007 by Jeff.

My father in law asked me to look at his utility bills today. It seems National Grid (our local utility - well sort of - they are British) just realized they were only billing him for natural gas delivery charges. His third-party gas supplier’s cut dropped through the cracks the past 4 months and just figured out they weren’t getting paid. The result? A $1700 surprise.

Their $500 gas charge for the month of February would pay for a year’s worth of heat at our house. He’s asked for advice, and there are some immediate things I suggested he can do.

The first is to lower the thermostat - he keeps it at 72 degrees day and night. So we’re installing a setback thermostat to lower the heat at night when he’s asleep. He’s older and likes it warm when he’s awake; the heat stays up during the day. Many people like it cooler, but I’m not willing to make that argument just yet.

The second thing we can do is close off unused rooms upstairs and turn off their radiators. It’s a really, really big house and large parts are only occupied during family gatherings. We can shut off the entire upstairs for most of the winter. I’m not too worried about freezing pipes. His heating pipes are all within the rooms (remember, it’s an old house - it predates central heat so the pipes were added later) and enough heat escapes the first floor to warm them. Ditto the bathroom pipes and toilets.

I noticed he still has an air conditioner in the dining room window. That’s a big, drafty hole in the wall. It’s way past time to take it out!

Remember that setback thermostat? It’s going to replace the current thermostat, a 1960’s round Honeywell unit in the back hallway. Not only is it money-wasting technology, but it’s placed on an outside wall between 2 windows. I bet the heat runs 4 or 5 degrees warmer than the thermostat setting, given its chilly location.

I won’t go on about the old double hung windows and 1950’s storm windows, or the complete lack of attic insulation. Spring is almost here, and those are projects for next fall.

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