THE SHORT ANSWER
Most main support beam replacements fall somewhere between $2,000 and $10,000.
Angi's July 2026 cost data puts the average project near $3,250. That is a useful starting point, but it does not mean that every damaged beam is a $3,250 job.
A beam in an open crawl space may be fairly easy to reach. A beam hidden above a finished basement ceiling is a different job. One may need a simple wood or LVL replacement. Another may need steel, new posts, stronger footings, plumbing moved out of the way and drywall repaired when the work is done.
That is why I would look at the scope before looking too closely at the average. The beam matters, but the work around the beam is often what separates a modest repair from a five-figure project.
WHERE THE MONEY GOES
The beam itself may be one of the cheaper parts of the job.
This surprises people because beam materials are often priced by the foot. Angi currently lists LVL around $3–$12 per linear foot, natural wood around $5–$30, glulam around $6–$40 and steel around $6–$20.
Those are material prices. They are not replacement prices.
Before an old main beam can come out, the weight above it usually needs temporary support. The contractor may also have to open a ceiling or wall and move plumbing, wiring or ducts. Then the old beam has to come out and the new one has to be moved into place.
Temporary support
The house still needs support while the old beam is being removed. Shoring can be a meaningful part of the labor.
Getting to the beam
An exposed beam is easier. Drywall, ductwork, wiring, plumbing or very low crawl-space access can slow the job down.
Removing the old beam
A long beam does not always slide neatly out of a house. Cutting, handling and disposal take time.
Installing the new one
Length, weight and material affect how many people and what equipment are needed to get the beam into position.
Putting the house back together
Drywall, trim, paint, flooring and utilities may sit outside the structural contractor's base price.
WOOD, LVL, GLULAM OR STEEL?
You normally do not choose a replacement beam from a price list.
The new beam has to carry the weight above it safely. It also has to work across the distance between its supports. That is why the cheapest material is not automatically the right choice.
LVL is engineered wood. It is common in residential framing because it can carry heavy loads without needing a piece of solid timber of the same size.
Wood may make sense in some houses, especially where the existing structure already uses large timber members.
Glulam is made from layers of wood bonded together. It can handle larger spans and loads than ordinary dimensional lumber.
Steel can carry a lot of weight with a relatively compact beam, but delivery, handling, connections and support below it can add to the installed cost.
These material prices come from Angi's 2026 support-beam data. They are useful for comparing materials. They should not be multiplied by beam length and treated as a contractor quote.
WHY BEAMS NEED REPLACEMENT
A beam can fail for several reasons, and the reason matters to the repair.
Not every damaged beam reaches the end of its life in the same way. Some slowly rot after years of moisture. Others are damaged by insects. A beam can also split, sag or turn out to be too small for the load it has been carrying.
Water and rot
Wood that stays damp can lose strength over time. Replacing the beam without fixing the water problem can leave the new wood in the same conditions that damaged the old one.
Insect damage
Termites and other wood-damaging insects can weaken a beam from the inside. The visible damage may be only part of the problem.
Splitting or serious cracking
A small surface crack is not the same as a deep split through the beam. The location and depth of the damage matter.
Old changes to the house
Walls may have been removed, openings enlarged or framing changed during an earlier remodel. Sometimes the existing beam is simply being asked to do more than it was designed to do.
The cause matters because replacing damaged wood is only half the job if the same problem is still present. If water caused the rot, the water needs attention too. If a support below the beam moved, that support needs to be checked before the new beam goes in.
REPAIR OR REPLACE?
A damaged beam does not always mean the whole beam has to come out.
Local damage can sometimes be repaired or reinforced. That may make sense when the problem is limited to one area and the rest of the beam is still sound.
Full replacement may make more sense when damage affects most of the beam. It can also be the better option when the beam has badly changed shape or is no longer suitable for the job.
The damage is limited, the rest of the beam is in good condition and there is a clear repair plan for the affected area.
Damage is widespread, the beam is badly weakened, or the proposed repair would leave too little reliable structure in place.
I would be cautious with a quote that simply says “beam repair” or “beam replacement” without explaining why that option was chosen. The useful question is not which word appears on the estimate. It is what condition the contractor found and what the proposed work is meant to fix.
WHAT THE JOB ACTUALLY LOOKS LIKE
A main beam replacement is usually a support-first, remove-second job.
The exact sequence depends on the house. But the basic idea is simple: the house needs temporary support before the old beam can come out.
- 1Confirm what needs to be replaced.
Rot at one end of a beam is different from a beam that is split, undersized or failing along most of its length.
- 2Work out the new beam size and support points.
This is where beam material, span, loads, posts and local requirements come into the picture.
- 3Support the structure temporarily.
Temporary walls, posts or other shoring carry the load while the permanent beam is out.
- 4Remove the damaged beam.
Access is important here. A contractor may need to work around plumbing, wiring, ductwork or finished surfaces.
- 5Set and connect the new beam.
The beam has to sit correctly on its posts or supports. It also needs to connect properly to the framing above it.
- 6Remove temporary support and repair disturbed finishes.
The structural job may be finished before the ceiling, flooring, trim or paint is restored.
ACCESS CHANGES EVERYTHING
The same beam can cost much more when the contractor cannot reach it easily.
HomeGuide's current crawl-space data puts many support-beam replacements around $1,500–$4,000. That can make sense when the beam is exposed and the rest of the support system is in reasonable condition.
But crawl spaces can also be difficult places to work. Some are barely high enough to move through. Others have plumbing, ducts, moisture or soil that makes moving a long beam into position much harder.
HomeGuide notes that rare, very long beams supporting a large part of a house can reach $10,000–$20,000. Angi also shows that difficult jobs can cost much more than the normal range.
Less demolition, fewer obstacles and simpler handling.
Access, shoring and restoration become bigger parts of the bill.
The project can move into five figures even when the beam material itself is not especially expensive.
LOOK BELOW THE BEAM
A new beam does not fix a bad post or a weak footing underneath it.
A main beam rests on posts, columns or other supports. Those parts matter too. If one of them is damaged or moving, a new beam alone may not solve the problem.
This is also where beam replacement can start to overlap with a larger foundation project. A damaged beam in an otherwise stable house is one job. A beam sitting on settled piers is another.
If the low floor above the beam is what first brought you here, the sagging floor repair cost guide explains how joists, beams, posts and foundations can create similar symptoms.
For homes built on this type of support system, the pier and beam foundation repair guide covers pier movement, leveling and broader foundation work.
ENGINEERING AND PERMITS
Budget for someone to decide what the new beam needs to carry.
Angi's 2026 main-support-beam guide suggests budgeting about $350–$750 for a structural engineer. Permit costs vary by location and can add more.
I would not treat that as paperwork that can always be removed from the quote to save money. The beam size, material, distance between supports and support points need to make sense for the actual house.
Local requirements are different, so a national cost guide cannot tell you which drawings, inspections or permits your property will need.
THREE VERY DIFFERENT PROJECTS
These examples show why one national average cannot describe every beam.
They are planning examples, not contractor quotes. The point is to show what pushes a project toward the low or high end of published cost ranges.
One damaged beam, clear access, supports remain usable
This is the kind of project that can sit closer to HomeGuide's $1,500–$4,000 crawl-space beam range. The beam is exposed and there is less finish work to undo.
Temporary shoring, full replacement and some work around utilities
This fits more naturally inside Angi's broad $2,000–$10,000 replacement range. Access and labor matter at least as much as the price of the beam.
Long beam, tight access and changes to posts or footings
Five figures becomes much easier to understand once the job includes more than swapping one piece of framing for another.
BEFORE YOU COMPARE TOTALS
I would want these seven things to be clear in a beam-replacement quote.
- Which beam is being replaced?
Length, size and location should be clear.
- Why does it need replacement?
Rot, splitting, pests, movement and an undersized beam are different problems.
- What is the new beam?
The proposal should identify the beam material, type and size.
- How will the house be supported during the work?
The quote should explain how the house will be supported while the old beam is out.
- Are the posts and footings staying?
Footings are the bases under the posts. If either needs work, that can add a lot to the bill.
- What happens to plumbing, wiring and ducts?
Find out whether moving and reconnecting them is included.
- Who repairs the finishes?
Drywall, flooring, trim and paint can become a second bill.
KEEP THE SCOPE STRAIGHT
Main support beam replacement is not the same thing as fixing every sagging floor.
A floor can sag because of damaged joists, a failed beam, bad posts, settled piers or movement farther down in the foundation. This page is about the case where the beam itself needs replacement.
It is also not a general foundation-repair guide. If the beam is sound but the structure below it has moved, the repair belongs to a different part of the house.
Keeping those jobs separate is important for cost comparison. Two contractors can look at the same sloping floor and give very different prices. One may be pricing a new beam. The other may be pricing repairs to the supports underneath it.
HOW WE BUILT THIS 2026 COST GUIDE
We kept replacement costs separate from beam-only material prices.
Our main price reference comes from Angi's July 2026 guide to main house support-beam replacement. We also compared Angi's 2026 beam and steel-beam cost data with HomeGuide's current crawl-space and pier-and-beam repair guides.
We did not average every number together. A $3–$12-per-foot LVL material price and a $2,000–$10,000 replacement project measure two different things. Mixing them would make the estimate less useful.
All figures on this page are national planning ranges. Labor, engineer fees, permits, beam design and access costs vary by house and location.
Replacement range, average project cost, material prices, contractor costs and structural engineer fees.
Beam materials, demolition, site prep, access and installation costs.
Crawl-space support-beam and pier-and-beam replacement cost ranges.