High-Efficiency Gas Boilers vs. Standard Efficiency Gas Boilers: Pros, Cons & Projected Utility Savings

Last Revised: 2/27/25 

Have you ever looked at your heating bill and wondered how much of an impact your boiler’s efficiency has on your wallet? You’re not alone. Many homeowners struggle to decide between standard efficiency and high-efficiency gas boilers – you may be torn on whether to prioritize lower upfront costs or long-term energy savings. 

At Mattioni, we’ve been guiding homeowners through heating decisions for over 75 years – because choosing the right boiler isn’t just about staying warm. It’s about making a smart investment in your home’s comfort and efficiency. 

In this guide, we’ll break down the key differences between standard and high-efficiency gas boilers, helping you weigh short-term vs. long-term costs. We’ll compare efficiency ratings, cost trade-offs, and projected utility savings so you can make the best decision for your home. By the end of this article, you’ll understand exactly how each option affects your finances, energy usage, and comfort. 

Standard Efficiency Gas Boilers 

If you’re looking for a traditional and reliable heating system, standard efficiency gas boilers have been a go-to for decades. While they may not be the most energy-efficient option, they’re straightforward, cost-effective upfront, and easier to maintain. 

• AFUE (Annual Fuel Utilization Efficiency): 80-89% (80-89 cents of heat per dollar of fuel) 

• How They Work: Uses a single-stage burner and a chimney vent pipe to expel combustion gases 

• Pros: Lower upfront cost, simpler technology (less dependent on maintenance) 

• Cons: Higher energy bills over time, less consistent heating performance, less environmentally friendly, require chimney vents (which may pose limitations if you don’t already have one) 

High-Efficiency Gas Boilers 

For homeowners looking to save on energy bills and reduce their carbon footprint, high-efficiency gas boilers are a smart investment. These units are more expensive upfront but utilize newer, more advanced technology to extract more heat from the fuel, making them more cost-effective in the long run. 

• AFUE: 90-98% (more heat goes into your home instead of escaping) 

• How They Work: Uses two-stage or variable-speed burners to throttle fuel usage and condensing technology to capture heat from exhaust gases before they exit the system 

• Pros: Lower energy bills, better for the environment, may qualify for rebates, longer lifespan (with proper maintenance) 

• Cons: Higher upfront cost, requires PVC ventilation instead of a chimney vent (oil boilers must keep chimney vent) 

Projecting Utility Savings: Your Boiler is Only One Part of Your Gas Bill 

Getting a high-efficiency gas boiler will keep your gas bill lower than if you were to install a standard efficiency one. But how big of a difference does it make? The answer is subjective to a lot of things: 

• How much do you cook with gas? 
• How much hot water do you use? 
• How warm do you like the house in the winter? 
• How good is your insulation? 
• How good are your windows? 
• How harsh are your winters? 
• Do you have a gas fireplace? 

Understanding how your boiler’s efficiency impacts your gas bill starts with knowing that it’s only one part of the equation. In other words, you use gas in other parts of your home. Consider that even though you only use your boiler for heating during the late fall, winter, and early spring, you still have a gas bill in the summer.  

Projecting savings is far from an exact science, however when comparing two boilers we can do some calculations. Let’s compare a 95% AFUE variable-speed boiler with an 80% AFUE single-stage boiler. That’s a difference of 15% efficiency, which can be used directly to find savings based on the initial gas bills experienced with the less efficient model. 

If your gas bill is $150 during the summer and $300 during the winter, that means your 80% boiler is responsible for $150 of the bill. The summer portion of the bill doesn’t go away in the winter – this is gas used in cooking, heating water for showers, and more. Now that we know that the boiler’s expenditure is $150 (as long as you don’t have a gas fireplace or other heat source), we can see that by upgrading to the 95% boiler, you’ll see savings of 15% – which equates to a $22.50 reduction in your gas bill. 

To be clear – projecting energy savings is not an exact science. This example takes place in a vacuum and doesn’t account for how our habits change with the seasons. It also doesn’t consider that two-stage and variable-speed systems produce more consistently comfortable temperatures in your home. But it can give you a starting block to do some quick calculations by referencing your average gas bills first and then comparing differences in efficiency.  

Check out this ROI calculator to discover how much your boiler can save on gas bills over the course of 12 years 

Which Gas Boiler Is Right for You: Standard Efficiency or High-Efficiency? 

So, which boiler is right for you? That depends on your priorities. If you’re focused on lower upfront costs and a simple, reliable system, then a standard efficiency boiler might be the way to go. However, if you want better heating performance, utility savings, and you value eco-friendly options, then a high-efficiency boiler is the smart choice. 

Still unsure? Our expert technicians can evaluate your home, walk you through your options, and install the perfect system to keep you warm and comfortable. At Mattioni, we’ve been helping homeowners balance short-term costs with long-term savings for over 75 years.  

Schedule your consultation today and get expert advice and a hassle-free installation process. Call us now at (610) 400-8510 or book online to enjoy a warmer, more energy-efficient home.