Attic Insulation Services
Attic Insulation Services in Marin, Sonoma & Napa County
The heat in your home is a moving force that will always flow to colder pockets. Warm air from your furnace, boiler, or heat pump escapes through cracks, heading toward cooler areas until there is no longer a temperature difference. In the summer, heat flows directly from the outdoors into your air-conditioned home.
Insulation is a protective barrier to prevent heat from leaving or entering your home. It keeps you comfortable and helps control your climate. Insulation maintains the indoor temperature, reduces outdoor noise levels, and protects your indoor air quality (IAQ) from outside pollutants.
Family-owned and operated, Ongaro & Sons has been helping homeowners in the North Bay since 1932. We serve customers in Marin, Sonoma, and Napa counties.
Why Reinsulate?
Your older home might have a lot of charm, but let’s face it, things can get drafty. Prior to 1980, building codes for home insulation were practically nonexistent. Here are a few telltale signs that reinsulation will help:
- Rooms feel hot and stuffy in the summer.
- You feel drafts in some rooms.
- Your HVAC runs nonstop during peak seasons.
- Your allergies flare up inside your home.
Reinsulation adds comfort to your day and saves you money on your heating and cooling bills. Where to start? The most effective places to reinsulate in an existing home are the attic, crawl spaces, basement, and exterior walls. Doing so will add more comfort and lower your energy bills.
Insulation Services in California
A well-insulated home is a money saver. The U.S. Department of Energy (DOE) notes that adding insulation to attics, floors, and crawl spaces can reduce your heating and cooling costs by up to 20 percent.
At the same time, the North American Insulation Manufacturers Association (NAIMA) estimates that approximately 90 percent of U.S. homes are under-insulated. Schedule an appointment with Ongaro & Sons today to learn how adding insulation can help create a healthy home.
Our team at Ongaro & Sons will air seal and insulate your home to ventilate properly, keep out pollutants, and improve your IAQ. We take great care in our craftsmanship and will show you how we plan to proceed beforehand.
Types of Insulation
Choosing the right type of insulation is key to maximizing your home’s energy efficiency and comfort. Here are some of the most common insulation materials we offer, each suited to different spaces and performance needs.
Spray Foam Insulation
Spray foam insulation sets the gold standard. It keeps out the elements (including moisture), creates an airtight seal, and is environmentally friendly. Spray foam sets quickly and is easy to apply. It has an advantage over other forms of insulation because it can fill tight crevices.
Homes insulated with spray foam enjoy better protection against mold and mildew. It also creates a natural sound barrier so you can enjoy your quiet time.
Fiberglass Insulation
Fiberglass insulation is a great option for just about anywhere, exterior walls, floors, ceilings, attics, basements, and other areas of your home. You commonly find it in blanket form, called batts. Homebuilders love fiberglass because it is easy to use and poses no fire threat. Plus, it is a terrific thermal insulator. Fiberglass is made from fine glass particles and can be a skin and lung irritant, so always wear protective clothing and eyewear if you plan to install it.
Cellulose Insulation
Cellulose is loose-fill or blown-in insulation, typically made from recycled paper products. It offers a sound solution for insulating existing finished areas in your home or irregularly shaped areas. It is relatively inexpensive and is usually treated with borates that repel insects and vermin. Plus, it is treated with fire retardants to meet federal and state fire safety guidelines.
Retrofit Insulation
Chances are that the older home you just moved into is not well insulated. Retrofit insulation refers to retrofitting your home with insulation. Your home may have too many drafty spots or air leaks, or your energy bills keep going up. Those are signs you may want to consider reinsulating your home. Sometimes, more than one type of insulation material is necessary.
Comprehensive Insulation Solutions
We offer comprehensive insulation solutions for every area of your home:
- Attic Insulation: Heat rises, so don’t let it escape through your attic. We offer top-grade blown-in or batt insulation to seal your home’s upper level and prevent energy loss.
- Wall Insulation: Insulating walls adds a critical barrier between your indoor spaces and outdoor elements, reducing heat transfer and increasing comfort.
- Crawl Space and Basement Insulation: Damp, poorly insulated crawl spaces can impact the entire home. We use specialized insulation techniques to protect from moisture, improve airflow, and prevent mold.
- Insulation Upgrades and Retrofits: Have an older home? Upgrading outdated insulation can lead to immediate energy savings and a noticeable boost in comfort. We evaluate your current setup and recommend the best course of action.
Choosing Insulation for Your Marin, Sonoma & Napa County Home
Here are a few factors to consider when choosing insulation:
What is R-value? The R-value indicates how well insulation material can reduce heat flow between the inside and outside of your home. For example, the value R-30 means it takes approximately 30 minutes for the heat to radiate through that insulation. The greater the R-value, the more the heat flow is reduced.
Why spray foam? Spray foam insulation can expand and tightly fill any difficult crevices in your home. It creates an airtight seal, giving it an extremely high resistance value. It offers the perfect solution to protect your home if you live in a colder climate. The benefits of spray foam insulation include:
- Thermal Resistance: Enjoy lower heating and cooling costs. Spray foam fills gaps and voids to create a barrier that prevents energy loss. It also provides a superior R-value.
- Moisture Barrier: Controls moisture to help prevent mold, mildew, and bacterial growth. Plus, it keeps out dust and other pollutants to maintain a healthy indoor air quality (IAQ).
- Air Barrier: Creates a seamless insulated barrier to reduce outside noises.
Open-cell vs. closed-cell spray foam: Each of these different types of spray foam insulation has its advantages. Open-cell foam is a much more flexible option for insulating those hard-to-reach nooks or crannies. Closed-cell foam is much more rigid and stable. It’s perfect for tight spaces and can add to the structural integrity of any wall. Plus, it helps prevent water and moisture from getting inside your home.
Our licensed experts at Ongaro & Sons can show you how a detailed thermographic scan of your home can illustrate your home’s heat distribution and illuminate areas to reinforce.
Schedule Your Attic Insulation Service
Our team at Ongaro & Sons can answer all your questions about insulating your home in Penngrove, Larkfield-Wikiup, Corte Madera, or any surrounding area of the North Bay. We proudly serve Sonoma, Marin, and Napa counties. Call us now at 415-741-2820 or book your appointment online for reliable insulation service you can trust.
Your Comfort, Our Priority
Ongaro & Sons is your trusted heating, cooling, plumbing, electrical, and solar expert, specializing in reliable maintenance and repair services that keep your home running efficiently year-round.
Our certified technicians deliver unmatched expertise with fast, friendly service across Marin, Sonoma and Napa County. From HVAC tune-ups to plumbing repairs and electrical upgrades or solar solutions, we focus on energy-efficient performance and long-term comfort. Count on us to maintain the systems that power your home and keep your environment just the way you like it.
Licensed, Insured, Background-Checked
Our technicians are licensed, experienced, and trained to service all makes and models.
Locally Owned and Operated
Serving the Napa, Marin, and Sonoma communities with personalized, hometown service.
Reliable Repairs
We respond quickly and get the job done right the first time, with no surprises.
Since 1932
Why Ongaro & Sons for Insulation
Insulation is an HVAC decision, because it changes the load the equipment has to meet.
Schedule Service →Air sealing before adding depth
Insulation slows conduction. It does not stop air movement. Adding depth over an unsealed attic floor buys much less than the label suggests.
The load calculation gets redone
Improving the envelope lowers the load, which can change what size equipment the house needs. Doing insulation and equipment in the wrong order means paying for capacity you no longer need.
Ducts in the attic considered as part of the same problem
If the distribution runs through the attic, what happens up there matters more than in a house with ducts in conditioned space.
Ventilation kept intact
Blocking soffit vents while insulating causes moisture problems that surface later. Baffles and clearances are part of doing it properly.
Envelope and equipment under one licence holder
Because we also fit the system, the load calculation gets revisited once the envelope improves, instead of leaving you with equipment sized for the old house.
Discount
Membership
Ongaro Maintenance Plans
Annual maintenance on your home systems provides safeguards and comfort to you and your family. Members get priority scheduling, discounts, and proactive checkups that catch problems early.
Member Discounts
5% off every repair and replacement, all year long.
Peace of Mind
Proactive checkups catch issues before they become big problems.
Courtesy Reminders
We call you to schedule: never miss a seasonal service.
Value That Lasts
With Ongaro & Sons, you’re investing in quality, integrity, and service that stands the test of time. Explore our current promotions and see the difference real value makes for your HVAC, plumbing, and electrical needs.
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Read MoreFrequently Asked Questions
Can insulation help with noise reduction?
Yes, insulation not only improves energy efficiency but also acts as a sound barrier. Adding insulation to interior walls, floors, and ceilings can significantly reduce noise between rooms or from outside sources.
Can the type of insulation I choose affect my health?
It’s possible if it’s not installed correctly. Poorly installed insulation can lead to itchy eyes, a skin rash, or unpleasant odors that make it difficult to breathe comfortably. Additionally, some types of insulation should not be used in damp crawl spaces, for example, because they will not cure properly. That can lead to extended periods of off-gassing. You can rest assured that our experienced installers at Ongaro & Sons never rush a job or try to install insulation into the wrong area.
How do I know if my home needs more insulation?
Signs include high energy bills, uneven temperatures between rooms, drafts, cold walls in winter, and hot ceilings in summer. An insulation audit or energy assessment can help determine where improvements are needed.
What areas of my home should be insulated?
The most important areas include the attic, walls, crawl space or basement, and floors above unheated spaces. Proper insulation in these areas helps regulate temperature, reduce energy costs, and improve comfort year-round.