How to SAVE on ENERGY????
Property Manager · Rockville, MD · Member since 2014 · 287 posts · 29 votes
Problem...... - Utilities From HELL!!!!
My client has the property from hell, with an old-school forced air furnace.....
I was able to get them great tenants at a great rate..... only to find the blood sucking heat drain it all away....
Bills go up to $500/mo!!!.....
I'd like to consult my client with an alternative, because the house has HUGE potential.....
Maybe some of you guys r smrtr than I..... any ideas?
@Atwan Kwan that seems like a really high gas bill. Can you provide more detail on the property like age, square feet, furnace age, is it single or multifamily, etc? Replacing the thermostat with a digital programmable type is a good first step. Next look at the furnace. You could have a 70% or worse efficient furnace and a new one could be 95% or better. The furnace upgrade could pay for itself quickly. You get to depreciate it on your taxes. Check the attic first because that is where most of your heat escapes. Should be 18" or more of insulation in the attic. If not, having insulation blown is cheap and fast. Once you start getting into windows, it is going to help but will cost lots of money up front.
Just to summarize in order. Thermostat upgrade, furnace upgrade, attic insulation, windows.
One final caution is that tenants who do not pay their own heat will often be careless. I had a property where I paid gas and I drove by in January to find all the upstairs windows open. They said it was hot so they opened the windows. Whenever possible have the tenant pay all utilities and you will be amazed how much the bills decrease.
@Roy N., of course it's colder in Canada, I never said anything about that. The OP is from Maryland, I'm assuming the property is as well... and I stand by my original point. Actually I just checked, Baltimore Maryland is warmer than Kansas City.
Again discount the hundreds of projects I've ran heat loads on in the US if you want. But I have basis for my reasoning. If his property is somewhere with extreme temperatures, then it can change things.
Dustin:
I hear you and it's an interesting proposition. In an area that has marginal heating/cooling loads it may be feasible. It would definitely be cheaper during the build/renovation, but I'm just not convinced it would be a better/cheaper over the longterm when you consider operational costs.
In a moderate environment it is fairly straightforward to be able to eliminate the need for conventional HVAC during a new build. It's a little more challenging during retrofit and will only be cost-effective to go so far.
When I get some time, I'll create a dataset and model a house with well sealed, but uninsulated wall assemblies in a moderate environment just out of curiosity.
This advice for reducing heating and cooling costs in older homes may be of some help.
https://www3.epa.gov/region5/sustainable/pdf/Energy-advice-for-owners-of-older-homes.pdf
Look into foam insulation blown into the roof rafters. It runs about ~$2/sqft of the home and keeps it like an ice box. If it's multiple stories, then just the footprint. That, and make sure windows are caulked/foamed. Double pane and low-e are good options too.
This advice may be good for Texas,but in cold climates you do not want to blow foam insulation on the roof rafter unless you plan to make the attic livable space. Blowing insulation on the rafter will reduce the life of your shingles because it prevents temperature from leveling between the inside and outside. You want to keep the temperature under the roof as close as possible to the temperature on the outside. For that reason you also want proper venting in an attic which means under soft vents and roof vents to keep air flow. Another thing to consider is that if your attic is properly vented, the heat would escape through the vents if you insulated the rafters versus blowing in fiberglass over the living space ceiling. I believe both methods have their place and it depends on climate and building construction which is applicable. I made my recommendation based on the assumption the property was local where the original poster lives.
This advice may be good for Texas,but in cold climates you do not want to blow foam insulation on the roof rafter unless you plan to make the attic livable space. Blowing insulation on the rafter will reduce the life of your shingles because it prevents temperature from leveling between the inside and outside. You want to keep the temperature under the roof as close as possible to the temperature on the outside. For that reason you also want proper venting in an attic which means under soft vents and roof vents to keep air flow. Another thing to consider is that if your attic is properly vented, the heat would escape through the vents if you insulated the rafters versus blowing in fiberglass over the living space ceiling. I believe both methods have their place and it depends on climate and building construction which is applicable. I made my recommendation based on the assumption the property was local where the original poster lives.
A little more elaborate than my curt response to Justin yesterday.
That said, you can insulate the underside of an existing roof deck. We done it in older (Second Empire/Queen Anne/Victorian) buildings around here that were built with closed soffits. It is often easier in a balloon framed house to bring the attic into the conditioned space than try to air seal the tops of all the walls.
However, if you do spray and insulate the underside of your roof deck in most any climate, but particular in a colder climate, you will also want to insulate the topside of the roof proportionately to ensure the roof deck remains in a narrow temperature band and you do not have condensation/moisture collecting in the roof deck.
When we do this, we then strap over the insulation with 2x4s to create a 1.5" cavity (the ventilation) then over roof - on the old buildings with their 7-9 pitch roofs we normally hang steel roofing directly on the strapping.
Look into foam insulation blown into the roof rafters. It runs about ~$2/sqft of the home and keeps it like an ice box. If it's multiple stories, then just the footprint. That, and make sure windows are caulked/foamed. Double pane and low-e are good options too.
This advice may be good for Texas,but in cold climates you do not want to blow foam insulation on the roof rafter unless you plan to make the attic livable space. Blowing insulation on the rafter will reduce the life of your shingles because it prevents temperature from leveling between the inside and outside. You want to keep the temperature under the roof as close as possible to the temperature on the outside. For that reason you also want proper venting in an attic which means under soft vents and roof vents to keep air flow. Another thing to consider is that if your attic is properly vented, the heat would escape through the vents if you insulated the rafters versus blowing in fiberglass over the living space ceiling. I believe both methods have their place and it depends on climate and building construction which is applicable. I made my recommendation based on the assumption the property was local where the original poster live
Joe what's the best type roof if you have an attic living space with blown insulation?
Look into foam insulation blown into the roof rafters. It runs about ~$2/sqft of the home and keeps it like an ice box. If it's multiple stories, then just the footprint. That, and make sure windows are caulked/foamed. Double pane and low-e are good options too.
This advice may be good for Texas,but in cold climates you do not want to blow foam insulation on the roof rafter unless you plan to make the attic livable space. Blowing insulation on the rafter will reduce the life of your shingles because it prevents temperature from leveling between the inside and outside. You want to keep the temperature under the roof as close as possible to the temperature on the outside. For that reason you also want proper venting in an attic which means under soft vents and roof vents to keep air flow. Another thing to consider is that if your attic is properly vented, the heat would escape through the vents if you insulated the rafters versus blowing in fiberglass over the living space ceiling. I believe both methods have their place and it depends on climate and building construction which is applicable. I made my recommendation based on the assumption the property was local where the original poster live
Joe what's the best type roof if you have an attic living space with blown insulation?
In my part of the country it is all asphalt shingles with blown insulation.
Are metal roofs impacted?
If you insulate directly on the underside of the roof deck, it is the decking that is effected, not the weather layer (at lease not directly). In the example I gave above, you could sheet overtop of the 2x4 strapping and lay an asphalt roof (we do that if the pitch is low - say 4/12 or less - enough you might actually need to get on the roof for snow removal).
I'll post stats again and yes the home is in Maryland close to DC
"4br/2ba raised rancher, with basement. 1,448 sqft, built in 1952, furnace is AT LEAST 15 yrs old.
Already put in new digital thermostat, given free by pepco (no help)...... it was originally a 2br/1ba with addition..."
@roy n. The basement (700+sqft) is in fact unfinished and uninsulated as well as the walls in the house. But if uninsulated walls don't make much of a difference in a sealed house, it's gotta be the basement?
What do you suggest I do to diagnose this? Pepco came in and didn't provide many options.
Regarding the bills, once again tenants are usually expected to pay, but they complained when bills got to $500 due to inefficient mechanicals so owner covered.... What would you do?
Now owner is so frustrated and wants to cash out, despite a prime location for easy rental and assured appreciation.
@Atwan Kwan how deep is the insulation in the attic? Also you mention $500 per month but that was in reference to heat. What is the situation with air conditioning as far as electric bill? You seem to refer to this as a continuing problem so it must affect cooling too. If that is the case, what is the age of the AC and is it central air?
It is hard to say on the furnace just based on age because 15 years ago there were very efficient furnaces being installed. I would hate to tell you that would solve the issue.
What does the furnace run on? Oil, natural gas or electric?
@Atwan Kwan I'm still betting the tenants have it set to a toasty 75 degrees (or higher) in the winter and 70 degrees (or less) in the summer 24/7.
This is based upon the assumption of a tight house and good attic insulation.
Again, point of reference. My house is a little smaller (1000 sqft main floor, 700 sqft basement), but not enough for 4 times the gas bill in the winter. I have no wall insulation. My furnace is probably 80% efficient (I am guessing there) and I live in a colder climate. This is redneck engineering, but it doesn't mean it's crazy, so let's back it out a little.
Your house is about 1.25x the size of mine. Let's assume my furnace is 90% efficient to be conservative. I looked at one site (might not be accurate) but it says gas prices there are about 35% higher. Ok, so my gas bill on the high side is about $125. Let's say $150.
So: $150 x 1.25 (for sqft) x 1.35 (for gas prices) x Z (energy efficiency ratio) = $500
Solving for Z would mean that the existing furnace would need to be 45% efficient. Now there absolutely are other factors that could alter my assumptions, but that is a huge margin for equipment efficiency differences.
Again, my advice is to check attic insulation, check equipment efficiency just to be sure, but then tell the tenants they need to turn the thermostat down. The third being the highest probability for the problem IMO.
Really clever problem solving here....
But of the answers I know off hand, i standby eliminating the tenant as wasteful.
these tenants have been some of the best ones, as very frugal and incredibly responsible. They don't know when (or if) the owner would pick up bill and have taken extra measure to keep HVAC off. It's really old electric forced air....
We looked into solar panels, but the roof of the addition wouldn't support the weight.
Really clever problem solving here....
But of the answers I know off hand, i standby eliminating the tenant as wasteful.
these tenants have been some of the best ones, as very frugal and incredibly responsible. They don't know when (or if) the owner would pick up bill and have taken extra measure to keep HVAC off. It's really old electric forced air....
We looked into solar panels, but the roof of the addition wouldn't support the weight.
Well that is your problem "electric forced air". Replace the furnace with natural gas high efficiency forced air and problem is solved. Sorry I should have asked if it was electric sooner. Electric is going to cost you the most regardless of age it is just less efficient. First thing to check is if the location has natural gas available. If not then oil or propane may be options.
@Joe Splitrock how much would you estimate that at? I think we already realized we can deduct that.
If not already understood, it's central air
@Dustin Beam is pointing you the right direction. In addition to his list, I would recommend you have someone go around and pick all the low hanging fruit: caulking (windows, doors, sills, plumbing/electrical/HVAC penetrations, baseboards and trim); weather stripping (doors and operable windows). If the walls themselves are not tight (almost a guarantee) look at putting gaskets behind switch/receptacle plates on external walls to stop drafts ... do the same with light fixtures if there is no effective vapour barrier to the attic. If the house has a chimney which is not longer required, plug it.
Once you have done the inexpensive to tighten the house, then you can consider changing fuels - here electricity, oil and gas are all about the same cost, but in many places in south in the U.S.A. gas is considerable cheaper. A new condensing gas furnace should be close to 95% efficient. If electricity is only marginally more than gas, then consider installing a heat pump with a central air-handler (HSPF 10-12, SEER 16 - 20). In comparison, traditional electric coils are almost 100% efficient at producing heat, even if more expensive to operate.
@Joe Splitrock how much would you estimate that at? I think we already realized we can deduct that.
If not already understood, it's central air
Electric is probably 3-5 times as much as natural gas would be. For example my highest gas bill last year was $140 and my home is much larger - also newer though. Newer central air units are also much more efficient, but it is still electric so not as much savings as the furnace will get you.
@Joe Splitrock how much would you estimate that at? I think we already realized we can deduct that.
If not already understood, it's central air
Electric is probably 3-5 times as much as natural gas would be. For example my highest gas bill last year was $140 and my home is much larger - also newer though. Newer central air units are also much more efficient, but it is still electric so not as much savings as the furnace will get you.
If you want/need central air, you can get heat-pump (or air-conditioning only) set-ups with the external compressor and a set of coils which install in the plenum of the furnace. This allows you to run the heat pump for cooling and/or heating in milder weather (where a good heat pump will have a COPS of 3+) and run the gas to do the heavy lifting in the colder months.
That said, regardless of how much you pay for heat, keeping more of it inside the building envelope for longer will save you the most long-term.
Really clever problem solving here....
But of the answers I know off hand, i standby eliminating the tenant as wasteful.
these tenants have been some of the best ones, as very frugal and incredibly responsible. They don't know when (or if) the owner would pick up bill and have taken extra measure to keep HVAC off. It's really old electric forced air....
We looked into solar panels, but the roof of the addition wouldn't support the weight.
Well that is your problem "electric forced air". Replace the furnace with natural gas high efficiency forced air and problem is solved. Sorry I should have asked if it was electric sooner. Electric is going to cost you the most regardless of age it is just less efficient. First thing to check is if the location has natural gas available. If not then oil or propane may be options.
Joe, I'm certain you know the difference but I want to make a small correction to your statement for others that may be reading.
Electric heat is extremely efficient. Like 99%+ efficient. But that doesn't mean cheaper. What you want to ask is "how much am I paying per btu or kW?". You can convert the two back and forth.
So say you have a 10kw electric heater. You're getting pretty much all that as heat in the home. That's about 34100 btu/hr. But to get equal heat, you have to divide gas furnace capacity but its efficiency . If 90% efficient, you need a furnace with a capacity of 34100/.9 which is about 38000 btu/hr. So then you compare what your gas prices in your area are too the electric prices.
Chances are gas is cheaper though, even if less efficient.
Really clever problem solving here....
But of the answers I know off hand, i standby eliminating the tenant as wasteful.
these tenants have been some of the best ones, as very frugal and incredibly responsible. They don't know when (or if) the owner would pick up bill and have taken extra measure to keep HVAC off. It's really old electric forced air....
We looked into solar panels, but the roof of the addition wouldn't support the weight.
Well that is your problem "electric forced air". Replace the furnace with natural gas high efficiency forced air and problem is solved. Sorry I should have asked if it was electric sooner. Electric is going to cost you the most regardless of age it is just less efficient. First thing to check is if the location has natural gas available. If not then oil or propane may be options.
Joe, I'm certain you know the difference but I want to make a small correction to your statement for others that may be reading.
Electric heat is extremely efficient. Like 99%+ efficient. But that doesn't mean cheaper. What you want to ask is "how much am I paying per btu or kW?". You can convert the two back and forth.
So say you have a 10kw electric heater. You're getting pretty much all that as heat in the home. That's about 34100 btu/hr. But to get equal heat, you have to divide gas furnace capacity but its efficiency . If 90% efficient, you need a furnace with a capacity of 34100/.9 which is about 38000 btu/hr. So then you compare what your gas prices in your area are too the electric prices.
Chances are gas is cheaper though, even if less efficient.
And just for the sake of more thought and complications. Heat pumps can yield an effective efficiency over the heating season of more than 100% (in comparison to traditional resistance heating) ... in a nice, mild climate like Maryland, a good heat pump should be able to produce an average effective efficiency of 200+%.
Get some contractors in there with suggestions and estimates so tenant knows you're doing something. Maybe more attic insulation will give biggest bang for buck, or duct cleaning, or changing the filter more often. Replacing a 15-year old furnace is not my first choice. Good to know tenant is responsible for bill, suggest year-round balanced billing to take out some of that winter sting.
Really clever problem solving here....
But of the answers I know off hand, i standby eliminating the tenant as wasteful.
these tenants have been some of the best ones, as very frugal and incredibly responsible. They don't know when (or if) the owner would pick up bill and have taken extra measure to keep HVAC off. It's really old electric forced air....
We looked into solar panels, but the roof of the addition wouldn't support the weight.
Well that is your problem "electric forced air". Replace the furnace with natural gas high efficiency forced air and problem is solved. Sorry I should have asked if it was electric sooner. Electric is going to cost you the most regardless of age it is just less efficient. First thing to check is if the location has natural gas available. If not then oil or propane may be options.
Joe, I'm certain you know the difference but I want to make a small correction to your statement for others that may be reading.
Electric heat is extremely efficient. Like 99%+ efficient. But that doesn't mean cheaper. What you want to ask is "how much am I paying per btu or kW?". You can convert the two back and forth.
So say you have a 10kw electric heater. You're getting pretty much all that as heat in the home. That's about 34100 btu/hr. But to get equal heat, you have to divide gas furnace capacity but its efficiency . If 90% efficient, you need a furnace with a capacity of 34100/.9 which is about 38000 btu/hr. So then you compare what your gas prices in your area are too the electric prices.
Chances are gas is cheaper though, even if less efficient.
And just for the sake of more thought and complications. Heat pumps can yield an effective efficiency over the heating season of more than 100% (in comparison to traditional resistance heating) ... in a nice, mild climate like Maryland, a good heat pump should be able to produce an average effective efficiency of 200+%.
I love heat pumps, but to pile on the complication :) they have their own limitations. Typically they will need a supplemental heat type if the weather gets below 35-40 degF for very long (which it will in Maryland). The heat pump can freeze up, and when it does, you either need to stop using it and use supplemental gas/electric heat, or you can run it in air conditioner mode and use the supplemental heat to raise the discharge air from the furnace to ~70degF until the heat pump thaws.
Really clever problem solving here....
But of the answers I know off hand, i standby eliminating the tenant as wasteful.
these tenants have been some of the best ones, as very frugal and incredibly responsible. They don't know when (or if) the owner would pick up bill and have taken extra measure to keep HVAC off. It's really old electric forced air....
We looked into solar panels, but the roof of the addition wouldn't support the weight.
Well that is your problem "electric forced air". Replace the furnace with natural gas high efficiency forced air and problem is solved. Sorry I should have asked if it was electric sooner. Electric is going to cost you the most regardless of age it is just less efficient. First thing to check is if the location has natural gas available. If not then oil or propane may be options.
Joe, I'm certain you know the difference but I want to make a small correction to your statement for others that may be reading.
Electric heat is extremely efficient. Like 99%+ efficient. But that doesn't mean cheaper. What you want to ask is "how much am I paying per btu or kW?". You can convert the two back and forth.
So say you have a 10kw electric heater. You're getting pretty much all that as heat in the home. That's about 34100 btu/hr. But to get equal heat, you have to divide gas furnace capacity but its efficiency . If 90% efficient, you need a furnace with a capacity of 34100/.9 which is about 38000 btu/hr. So then you compare what your gas prices in your area are too the electric prices.
Chances are gas is cheaper though, even if less efficient.
And just for the sake of more thought and complications. Heat pumps can yield an effective efficiency over the heating season of more than 100% (in comparison to traditional resistance heating) ... in a nice, mild climate like Maryland, a good heat pump should be able to produce an average effective efficiency of 200+%.
I love heat pumps, but to pile on the complication :) they have their own limitations. Typically they will need a supplemental heat type if the weather gets below 35-40 degF for very long (which it will in Maryland). The heat pump can freeze up, and when it does, you either need to stop using it and use supplemental gas/electric heat, or you can run it in air conditioner mode and use the supplemental heat to raise the discharge air from the furnace to ~70degF until the heat pump thaws.
Dustin:
There are several models of heat pump sold here in Canada which do not require supplemental heat until you reach -15C (5F) to as low as -25C (-13F). We use a particular Mitsubishi model which still operates at a COP of 2.5 at 0C (32F). Cold weather heat pumps use better (scroll) compressors with inverters to reduce the frequency of thaw cycles.
One of the most promising newer ideas for cold-weather is a Canadian designed heat-pump where the compressor sits inside and just the coil and fan assembly sites outside ... this eliminates the freeze up and allows prolonged operation at low (sub-freezing) temperatures.
Even in our nasty winters where we will have a week or two where temperatures do not climb above -20C and we are reliant on ancillary heat, the heat pump still comes out ahead over the entire heating season. [This is in an environment where there is marginal cost difference per Btu between gas, oil or electricity as a fuel].
@Roy N., fair enough, I'll have to look into those and educate myself.
@Dustin Beam thanks for the correction, bad choice of words on my part. You are correct it is not more efficient it is less expensive. Heating cost is relative to price of energy source, efficiency of heating device and cost of heating device. For example @Roy N. mentioned a heat pump and others mentioned solar. You have to look at the upfront cost and number of years to receive payback. In my market, heat pumps do not increase the value of a property, so the only way to gain benefit is to live in a house long term.
In my opinion heat pumps and solar do not make sense for rental properties. The reason is that you want to minimize your expense upfront. Run the comparisons, but ultimately I am pretty sure the electric furnace is the main problem and gas is the solution.