Replace Asbestos Siding: Remove, Encapsulate or Cover Over

If your house was built between the 1920s and the early 1980s and has stiff, gray-white shingles with a slightly dimpled or wood-grain texture, there’s a good chance it’s asbestos-cement siding. Deciding whether to replace asbestos siding starts with a surprising fact: intact asbestos-cement shingles are generally considered low risk as long as they’re left alone. The danger comes from breaking, cutting, drilling, sanding, or pressure washing them, which can release fibers you can’t see.

That leaves you four realistic options: patch damaged shingles, encapsulate the siding with primer and paint, side over it with new cladding, or have it professionally removed by a licensed abatement contractor. The right choice depends on the siding’s condition, your budget, local regulations, and whether you plan to sell or renovate soon.

This guide walks through testing, each option in plain terms, what the rules generally look like, typical costs, and when removal is the only sensible answer.

Should You Replace Asbestos Siding or Leave It in Place?

Start with an honest assessment of condition. Walk around the house and look for cracked, chipped, or missing shingles, crumbling edges, and areas damaged by lawn equipment or impacts. Asbestos-cement siding is dense and durable, and many 70-year-old installations still have 90 percent of their shingles intact. If yours looks like that, leaving it in place and maintaining it is often the lowest-risk and lowest-cost path.

Removal starts to make sense when damage is widespread, when you’re doing major remodeling that will require cutting into walls (new windows, additions, rewiring from the outside), or when you want a completely different look and don’t want the siding hidden under new cladding forever. Some buyers and lenders also prefer a house without it.

Quick Decision Guide

• Mostly intact, a few cracks: patch and paint (encapsulate).
• Intact but dated, want a new look, no major wall work planned: side over with a qualified contractor, if local rules allow.
• Widespread damage, crumbling, or major exterior renovation coming: professional abatement.
• Unsure what it is: test first.

Step One: Confirm It Is Asbestos

You can’t identify asbestos by looking. Fiber cement siding made today looks similar but contains no asbestos. The only way to know is laboratory testing.

An asbestos test kit lets you collect a small sample and mail it to an accredited lab (look for NVLAP accreditation). Many homeowners prefer to hire a certified asbestos inspector instead, because collecting a sample means breaking off a piece of material. If you do collect a sample yourself, follow the kit instructions closely: mist the area with water first, wear disposable gloves and a properly fitted N95 or better respirator, take a small piece from an already damaged edge rather than breaking a sound shingle, seal it in the bag, and wet-wipe the area and seal the spot with caulk or paint. Many state health departments recommend a professional for sampling, and some areas require it.

While you’re testing, think about lead too. Houses built before 1978 may have lead-based paint on the siding, trim, and windows. If you plan to scrape or sand old paint on the trim, test it with an EPA-recognized lead test kit or have a certified lead inspector check it. Any contractor who disturbs paint in a pre-1978 home should be EPA Lead-Safe certified.

What Not to Do With Asbestos-Cement Siding

These activities can release fibers and should be avoided unless done by trained, licensed professionals using approved work practices:

• Cutting, sawing, or grinding shingles
• Drilling or nailing through them
• Sanding or wire-brushing the surface
• Pressure washing or power washing
• Prying off and breaking shingles
• Scraping loose paint aggressively

Also don’t dump broken pieces in household trash. Asbestos waste typically must be wetted, double-bagged or wrapped, labeled, and taken to a landfill or transfer station that accepts it. Your state environmental agency or local health department can tell you the rules where you live.

Option 1: Asbestos Siding Repair for Cracked Shingles

Small cracks and chips are common, and minor asbestos siding repair is often possible without removing anything. The goal is to stabilize the damage without creating dust.

1. Mist the damaged area lightly with water from a spray bottle to keep any loose particles from becoming airborne.
2. Wear disposable gloves, safety glasses, and an N95 or P100 respirator.
3. For a hairline crack, fill it with a paintable exterior elastomeric caulk. Don’t scrape or grind the crack open first.
4. For a cracked shingle that is still attached, some contractors slide a thin piece of aluminum flashing behind the crack (under the course above) and seal the crack with caulk, which keeps water out without fastening through the shingle.
5. Wet-wipe the area with a damp disposable cloth, bag it, and dispose of it properly.

Replacing a broken shingle outright is a different matter. Removing it means pulling or cutting nails and often breaking the damaged piece, which is disturbance. Replacement shingles are available as salvaged asbestos-cement pieces or asbestos-free fiber cement look-alikes, but the removal step should be handled by an asbestos-trained contractor in most situations. Rules differ by state, so check before attempting any removal yourself.

Option 2: Encapsulate With Primer and Paint

Encapsulation means coating the siding to lock the surface fibers in place and protect the shingles from weathering. For siding in decent shape, it’s often the best value.

1. Clean gently. Use a garden hose at normal pressure, a soft brush, and a mild detergent solution. Never use a pressure washer.
2. Let it dry for at least 24 to 48 hours.
3. Prime with a high-quality acrylic masonry or bonding primer suitable for cement-based materials. Some products are marketed specifically as encapsulants.
4. Paint with two coats of 100% acrylic exterior latex. Apply by brush, roller, or airless sprayer.
5. Caulk gaps at trim and corners with paintable elastomeric caulk.

If the siding already has old paint that is peeling, don’t scrape it aggressively. Loose paint removal needs care — and if the paint is pre-1978, lead-safe practices apply too. A painter experienced with asbestos-cement siding is a good investment here. Expect a quality encapsulation paint job to last roughly 8 to 15 years before a recoat.

Option 3: Siding Over Asbestos Shingles

Covering asbestos siding with vinyl, fiber cement, metal, or engineered wood hides it and adds a fresh exterior. It’s cheaper than abatement and avoids removal, but it isn’t disturbance-free. New siding has to be fastened, and nailing through the shingles can crack them and create dust.

Contractors who do this well typically install vertical furring strips fastened into the wall studs, using wet methods and careful fastening to minimize breakage, then attach the new siding to the strips. Some local jurisdictions treat any fastening through asbestos material as a regulated activity, while others allow it with proper precautions. Ask potential contractors directly how they handle asbestos-cement substrate and whether they hold any required state asbestos training or licensing.

Keep in mind that siding over it doesn’t make the asbestos go away. Future window replacements, additions, or eventual demolition will still involve it. You’ll also need to disclose it when you sell in most states.

Option 4: Professional Removal and Abatement

If you decide to fully replace asbestos siding, hire a licensed asbestos abatement contractor. A typical removal involves:

• Notifying the state or local agency, if required, before work begins
• Laying heavy plastic sheeting on the ground around the house
• Keeping the siding wet with amended water throughout the job
• Removing shingles whole by pulling nails, not breaking them
• Wrapping and labeling waste for transport to an approved disposal site
• Cleaning up with HEPA vacuums and wet methods, followed by a visual inspection

Federal asbestos rules largely target commercial buildings and larger projects, and owner-occupied single-family homes are often exempt at the federal level. That doesn’t mean anything goes. Many states and cities have their own requirements for homeowners and contractors, including permits, notifications, and disposal rules. Call your state environmental or health agency before any removal work. Once the old siding is off, a regular siding contractor installs the new cladding, often with new house wrap.

Typical Costs

Prices vary widely by region, home size, and access, but general ranges look like this:

Abatement is usually priced per square foot of siding, and the cost of the new siding comes on top. Get at least three written quotes, and make sure each spells out disposal, cleanup, and air or visual clearance.

When to Call a Licensed Professional

Call a certified asbestos inspector if you’re unsure what the material is or need samples taken. Hire a licensed abatement contractor for any removal, replacement of individual shingles, or work involving extensive breakage. Bring in an EPA Lead-Safe certified contractor if you’ll be disturbing paint on a pre-1978 home. And contact your local building department and state environmental agency before siding over or removing, since permits and notification rules vary by location. When in doubt, leave intact siding alone until you have professional advice.