Brick Wall Lining Served as Insulation, Wind Barrier, Fire Blocking Brick Lined Walls in Wood Framed Homes
How to Detect Brick Wall Liner, What to do About "Brick Insulation" in Building Walls

  • BRICK LINED WALLS - CONTENTS: What is brick wall lining or brick "insulation" or "brick nogging" in buildings? What are the insulating properties of brick used in wall cavities? Why were bricks used to line the interior of some wood-framed buildings? How to identify the presence of brick wall lining materials and how to inspect this system for defects. How to repair brick-lined walls. What to do if part of your brick lined wall has fallen into the attic.
  • POST a QUESTION or READ FAQs about the properties, identification, & repair of brick nogging or brick-lined building walls.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Brick filled cavity walls in wood frame buildings:

This article describes brick wall lining or "insulation" in buildings, why it was used, what problems may occur, and the inspection methods and clues to detect brick lined walls in older homes (sometimes called Brick Nogging) and discusses the implications of brick wall liners in buildings.

Non-structural bricks were used to line the exterior walls in some pre-1900 wood frame buildings primarily an air infiltration or wind barrier, possibly as "insulation" or for thermal mass, and possibly as a "sound proofing" method.

Green links show where you are. © Copyright 2015, All Rights Reserved.

Brick Wall Lining in Older Homes: how to identify brick nogging

Brick Wall Lining Served as Insulation, Wind Barrier, Fire BlockingBrick wall "insulation" or brick nogging may be found in wood framed buildings built up to about 1900. Usually these homes have exterior clapboards and interior plaster walls.

Often these brick-lined wood-framed homes were built with balloon stud framing, no exterior sheathing (they used diagonal bracing), and exterior clapboards right on the studs. In homes framed in this manner, if the exterior wall cavities were left empty, the walls were drafty and uninsulated.

Some homes, such as the Weisman home in Montgomery NY (shown above) and another home photographed by Arlene Puentes (shown below), were built with brick-lined walls, bricks being mortared in between the studs on all floors and even extending into the attic.

Other benefits of this design included fire stopping effects and added thermal mass to the building, making temperature changes less rapid and thus the house more comfortable. The presence of brick in wood frame wall cavities, such as in the photograph shown at the top of this page (Courtesy Joe and Beth Weisman) may help determine the age of a building.

The condition of the brick "nogging" may also be an important indicator of the building leak history.

Also see BRICK VENEER WALL AIR LEAKS for a discussion of modern insulation methods for brick veneer walls.

An owner of such a home usually finds out about the brick in the home walls at the first renovation or wiring or plumbing project. But a home inspector and home buyer might also be able to detect brick-lined walls and should be interested in what this construction method might mean to the new owner.

These bricks are not structural, and they were simply mortared in place between wood framed wall studs and rested on the sill plates of each floor. It would be unusual to find brick wall linings in interior walls unless at one time the "interior" wall was at one time a building exterior wall structure.

Visible in the attic, Brick Wall Lining Served as Insulation, Wind Barrier, Fire Blocking

Brick Nogging was generally not intended to be exposed to view, and served the purpose of blocking wind that blew through older homes constructed without an exterior sheathing - clapboards were nailed directly to the structural frame. Typical wall construction was stud framing, 16" o.c., diagonal wood bracing in walls, clapboard exterior, rough masonry wall filler on all floors and extending into the attic. Interior walls were covered by plaster on wood lath.

Opening walls filled with brick nogging or other masonry will often reveal rough and varying styles of masonry (as it was not intended to be seen) that went in fast. The masons may have used a variety of bricks and rubble. I [DF] suspect that this construction method may have been adopted by builders who had observed the short life and pest infestation problems that followed colonial and later attempts at wall insulation using natural materials like straw and corncobs.

Websters Dictionary gives this definition: "Nogging: (?), n. Rough brick masonry used to fill in the interstices of a wooden frame, in building."
Wordnet Dictionary gives this similar definition: "Noun 1. nogging - rough brick masonry used to fill in the gaps in a wooden frame". "Nogging" is a term also used by some to describe exposed brick lining in timber framed walls in which the brick is left in view on the building exterior for aesthetic reasons.

Because brick (or other masonry) placed in building cavities as a wind barrier and thermal mass source was in that use not intended to be exposed, you can expect to see the workmanship quite rough in appearance and inconsistent from one building area to another (as any and various masonry material at hand might be used) compared with masonry intended to be left exposed to view.

Some Considerations for Homes with Brick Lined Walls - Brick Nogging

  • House Age: Brick nogging helps set a possible age for the home. Houses built between 1810 and 1900, or perhaps earlier may have brick-lined walls. I [Friedman] found brick nogging lining the walls of a 1790 house in Poughkeepsie NY. So finding bricks in your house walls is often a clue about when it was built.
  • Insulating Value of Brick Wall Lining: Brick has an "R" value estimated at about 0.11", so a brick lined wall has an R-value of something like R1 overall (including the wood siding and interior plaster) - pretty low compared with modern R11-R20 walls.

    Adding conventional insulation such as fiberglass batts, blown-in fiberglass, or blown-in cellulose or foam (to save heating and cooling costs) are not an option unless walls are stripped from inside or outside first, and bricks removed. In an extensive old house renovation, if the project includes replacing exterior siding or interior wall surfaces, and in homes where accurate historic preservation of original construction materials and details is not a requirement, it is common to remove all of the wall-lining bricks in order to substitute a more effective insulating material. Owners who have taken this step (such as the Weismans) report a significant reduction in home heating costs.
  • Weight of Brick-Lined Walls: Alan Carson, (Carson Dunlop Associates, Toronto) estimates that weight would be about 400 lb. per stud cavity per floor. (Clay bricks weigh about 150 lb./cu. ft.). If the structure is damaged by rot or insects, or modified by "remodeling" there is risk that the added weight of bricks in upper floor walls could require additional support. Beware of remodeling on lower floors which includes the removal of bricks in the wall cavities - it may be necessary to add support to be certain that weight of brick lining upper floor walls does not cause a structural problem for the lower floors.
  • Brick Wall Liners and Fire Safety: If the building was framed using balloon framing rather than platform framing it may be necessary to add fire blocking if bricks are removed since you may have removed what amounted to fire-blocking in the wall cavities.
  • Brick Lined Wall Collapse Warning: Joe and Beth Weisman pointed out at their website [References below] that when removing exterior siding [or interior plaster] one should be careful to watch out for falling bricks. In their renovation one wall dumped quite a few bricks on the ground when it was opened.

    Puentes points out that in earthquake prone areas, "hidden" brick or other masonry wall lining could fall into an upper room and perhaps through a ceiling into a room below, making this construction method an additional safety concern for houses in earthquake zones. [We don't know if this method has been used in earthquake areas.]
  • Brick Walls, Condensation, and Mold: Brick wall lining may increase condensation on the interior of some exterior walls and could be a dampness or mold issue. You may see evidence of this as mold behind pictures that have been hung on exterior walls for some time. You'll also see this in solid-masonry homes.
  • Electical Wiring: Running new electrical circuits in exterior walls will encounter the brick lining which may need to be removed in some cases (or run wires behind floor baseboards or in other chases). Carson wondered if the absence of electrical wiring (seen as no outlets nor switches) in the walls of an older building might suggest brick lining.

Where Will You Find Clues Suggesting the Presence of Brick Lined Walls

  • Age of the home: if the home was built before 1900 and is a wood frame structure, especially in cold climates where people care more about wind blowing through walls, brick nogging may have been used.

  • Visible in the attic, Brick Wall Lining Served as Insulation, Wind Barrier, Fire Blocking This photo shows the wall-cavity or interior surface of the exterior clapboard sheathing used on this home. The draftiness of walls constructed in this manner was a reason that some builders used brick wall lining as not only insulation but as "wind barrier".

    I f you look closely at the exposed side of the clapboards in this photograph where some wall lining bricks have conveniently fallen away, you'll see circular saw cut marks - an indicator that this house is not one of the older instances of brick wall lining. I estimate that this house dates from 1890.

    New York State had circular saw lumber mills sooner than some other states, and saw marks are not a precise dating method, but had this been a home from 1840-1850 we may have seen that the saw blade had left straight blade marks across the clapboard - indicating a power-operated vertical "pit saw."

    Had the saw blade marks been straight but alternating in a tight "X" pattern across the clapboard the board would have been cut on a hand-operated pit saw, and this would be a still-older home.

  • Brick Wall Lining Served as Insulation, Wind Barrier, Fire Blocking In the basement, bricks may be visible between floor joists sitting atop the building sills, especially in balloon-framed homes. Arlene Puentes' photograph shows how subtle this clue may be as very little brick may be visible from the basement.
  • In the living area - bricks may be discovered in wall cavities during renovations or remodeling
  • Mold on Walls: while certainly not a sure bet, the presence of mold behind wall hangings occurring on exterior walls may indicate the effects of brick lined wall cavities. The brick lining can mean that the surface of this wall stays cooler longer and has more condensation on the wall surface than will be seen on the surface of interior walls.
  • Sagging at Sills: At the interior side of exterior walls, usual degrees of sill or rim joist crushing in areas of rot or insect damage could include the added effects of the extra weight of bricks in the building exterior walls.
  • Visible in the attic, Brick Wall Lining Served as Insulation, Wind Barrier, Fire BlockingIn the attic - bricks may be visible between wall studs extending up into the attic. In this photograph of a brick-lined wall you can see that some of the bricks have fallen out of the wall cavity and onto the attic floor.

    This is not itself a structural problem but it may indicate a history of roof leaks at this spot. Roof leaks may in turn track to rot or insect damage.

    Based on this theory and buttressed by leak stains visible in the photograph, I'm guessing that these fallen bricks were on an eaves wall not a gable end wall.

    We discuss this further below at "Repairs".
  • Brick Wall Lining Served as Insulation, Wind Barrier, Fire Blocking Arlene's photograph of this brick-lined wood framed wall in an attic shows the diagonal bracing commonly used in this generation of wood frame brick-lined construction.

    The care with which the mason filled-in with brick and mortar even around the diagonal bracing confirms the intention of this usage as an air barrier.

  • Exterior Renovations: From the exterior - bricks may be visible if siding is removed for repairs or other building work


What to do if Portions of Your Brick Wall Lining Have Fallen into the Attic

  • Clean up the fallen masonry and debris.
  • Diagnose the reason that the bricks fell into the attic: the masonry wall filler may have been damaged by water from roof leaks or ice dam leaks if the home is in a northern climate. If this is the case you'll want to be sure you've corrected the cause of water leakage. If the brick collapse is traced to water leaks be sure to also look for evidence of structural rot of nearby wood framing members, and be alert for evidence of insect damage since leaks can attract carpenter ants or termites into a building, including an attic.
  • Consider rebuilding the brick liner in the wall cavity if you are not planning to renovate the area. Use soft mortar as was used originally. This option makes sense if only one or two bricks have fallen from place.
  • Alternatively, use modern insulation - especially where lots of wall-lining bricks have fallen or are loose and appear about to fall, insulate the wall empty wall cavity with other insulating material such as fiberglass batts.



Continue reading at THERMAL MASS in BUILDINGS or select a topic from the More Reading links shown below.


Suggested citation for this web page

BRICK LINED WALLS at - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

More Reading

Green link shows where you are in this article series.


Frequently Asked Questions (FAQs)

Click to Show or Hide FAQs

Ask a Question or Search InspectApedia

Questions & answers or comments about the properties, identification, & repair of brick nogging or brick-lined building walls..

Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

HTML Comment Box is loading comments...

Technical Reviewers & References

Publisher's Google+ Page by Daniel Friedman

Click to Show or Hide Citations & References