Replace Masonite Hardboard Siding With LP SmartSide
The hardboard lap on your 1970s to 1990s house is swelling at the bottom edges, flaking and going soft. It cannot be patched forever; here is how it gets replaced.
JMB Builders replaces Masonite hardboard siding with LP SmartSide lap siding across the Twin Cities and north metro. The swollen and rotting hardboard comes off, soft sheathing is replaced, the wall is wrapped and flashed, and new SmartSide lap goes on at a reveal close to the old one, with new trim at corners and openings. One wall or the whole house, priced per project from photos and a measure.
- Priced per project, per wall or whole house
- Hardboard off, sheathing checked, wall wrapped
- LP SmartSide lap at a matching reveal
- Painting quoted as its own line
- Licensed MN contractor BC809005
Hardboard siding, often called Masonite, went on a lot of Twin Cities houses from the 1970s into the 1990s. It is pressed wood fiber, and once the paint fails at the bottom edges and nail heads, it drinks water, swells, flakes and rots. The bottom course, the boards behind downspouts and the wall that gets the weather go first.
A few swollen boards can be swapped, but hardboard has not been made in the old profiles for years and patches rarely match. When rot shows on several walls, the job is replacement. LP SmartSide is an engineered wood lap that looks close to painted hardboard and comes primed; many owners pick it for that reason. Vinyl or fiber cement are the other choices, and we quote those too.
The work: hardboard off one wall at a time, the sheathing checked and soft sections replaced, house wrap and flashing at every window, door and penetration, then the new lap at a reveal close to the old one so the house keeps its look. Trim at corners, windows and doors is replaced in the same pass, since the old trim is usually hardboard too.
What you supply
- Photos of each wall and close-ups of the worst boards
- The house footprint or a rough wall-by-wall measurement; we confirm it on site
- Your color choice: factory-finished or primed for painting
- Whether you want one wall now or the whole house
What JMB supplies
- Removal and haul-away of the old hardboard siding and trim
- Sheathing repair where the hardboard let water in
- House wrap, window and door flashing, and flashing at every penetration
- LP SmartSide lap siding at a reveal close to the old one
- New corner, window and door trim, and blocks for lights, hose bibs and vents
- Clearance at roof lines, decks and grade, with kickouts where roofs meet walls
- Painting as its own line when you want it, and photos in your job folder
How it is priced: per project
Quoted in writing from your photos within one business day. What moves the number:
- Wall area and number of walls
- Sheathing rot found once the hardboard is off
- Number of windows, doors and penetrations to flash and trim
- One story or two, and access around decks and landscaping
- Factory-finished versus primed siding, and painting as its own line
- Trim replacement at corners, windows, doors and fascia
Photos of all four sides and a rough measurement get a firm quote per wall. Extra sheathing is priced per sheet on the quote.
How long it takes
One wall: one to two days. A whole one-story house: about one to two weeks depending on size, trim and weather.
How your project works
- 1
Send photos, get a written quote
Send three photos of the space and a sentence about what you want. You get a clear, itemized quote within one business day. We only come out to measure first when the job needs a tape measure — no pressure, no games.
- 2
Pick materials, or bring your own
We help you choose profiles and materials that fit the house and the budget, or match your existing millwork exactly — or you buy the door or trim yourself and we install it. Everything is confirmed before the crew is scheduled.
- 3
Clean, precise installation
The crew shows up on time, protects floors and furniture, and installs with tight joints and consistent reveals. Photos of the finished work go in your job folder.
- 4
Walkthrough and invoice
We walk the finished work with you. If anything is not right, we fix it before we call the job done. Then one invoice, paid by check or direct deposit — no card fees, no payment links.
Situations and options
One wall at a time
The weather side or the back wall first, when the rest of the hardboard still has some life. The new lap is set at the same reveal so the house does not look patched from the street.
Whole house
All the hardboard off, sheathing repaired, wrapped and flashed, new lap and trim all around. One mobilization and one color.
Hardboard to vinyl or fiber cement
Same tear-off and wall prep, different siding. Vinyl costs less and needs no paint; fiber cement is heavier and slower to install.
Replace Masonite Hardboard Siding With LP SmartSide: questions, answered
Can Masonite hardboard siding be replaced with LP SmartSide?
Yes. The hardboard comes off, the sheathing is checked and repaired, the wall is wrapped and flashed, and LP SmartSide lap goes on in its place. SmartSide lap looks much like painted hardboard, so the house keeps its look. We set the new lap at a reveal close to the old one.
Why is my hardboard siding rotting at the bottom?
Hardboard is pressed wood fiber. Once the paint fails at the bottom edges and nail heads, it soaks up water, swells and rots. The bottom course near the ground, boards behind downspouts and boards under roof edges without kickouts go first.
Can I just replace a few rotted hardboard boards?
A few, yes, but hardboard is no longer made in most of the old profiles, so replacement boards are a close match at best. When rot shows on more than a few boards or on several walls, replacing a whole wall with new lap looks better and lasts longer than spot patches.
Can you replace hardboard siding on just one wall?
Yes. The worst wall is replaced first with new lap set at the same reveal, painted to match the rest. Many owners do the weather side now and the others later. When the paint is matched, it reads as one house from the street.
Should I replace hardboard siding with vinyl or LP SmartSide?
LP SmartSide looks closest to painted hardboard and takes paint, so the house keeps its look; it needs its clearances and sealed edges to last. Vinyl costs less and never needs paint but looks different up close. Fiber cement is the heaviest and slowest to install. We quote whichever you choose, with the same tear-off and wall prep.
Does new LP SmartSide need to be painted?
It comes either factory-finished in a set of colors or primed for paint. Primed siding needs a finish coat soon after it goes up. Painting is quoted as a separate line, or leave it primed and paint it yourself.
Recent JMB work, from our job log
59 installs recorded across 30 Twin Cities communities since Dec 2025. Window and door installs for homeowners and for the builders and dealers we sub for. Counts come straight from our job log; no customer names.
Get a written quote for this job
Three photos and a sentence is enough. You hear back within one business day. Or text the photos to 763-204-2099.
Related jobs we do
LP SmartSide Siding Installation — Engineered Wood Lap and Panel
Engineered wood siding that looks like painted cedar and takes a hailstorm, installed with the sealed cuts, joint flashing and clearances that keep it that way through Minnesota winters.
Read moreLP SmartSide Swelling at the Bottom Edge — Board Repair
Some LP boards on the house are puffed up at the bottom edge or flaking where they meet the roof or deck. The rest of the siding is fine. Here is how those boards get fixed so they stay fixed.
Read moreVinyl vs LP SmartSide vs Hardie — Best Siding for Minnesota
Three sidings, one Minnesota winter, one hailstorm a summer. Here is how each one holds up, what it takes to install, and which we would put on your house.
Read moreReplace Siding on One Side of the House — Vinyl Matched or Swapped
One wall is faded, cracked, melted by a grill or beaten up by weather, and the rest of the house is fine. You want that wall redone without residing the whole house.
Read moreCorner Board Replacement — Rotted Exterior Corner Trim
The bottom of the corner board is soft, the paint is lifting in sheets, and the siding ends behind it are starting to go too. We replace the corner, flash it, and tie the siding back in so it stays dry.
Read moreBoard and Batten Siding Installation — Gable Accents and Whole Walls
The gables in board and batten and the rest in lap, or the whole house vertical: we lay out the battens so they land square at the corners and flash the panel joints so the look holds up to Minnesota weather.
Read morePage reviewed September 26, 2026 · JMB Builders LLC, MN license BC809005 · All siding pages
Where we work
Siding near you
Based in Zimmerman, scheduling across the Twin Cities metro. Closest first: