Definitions
A |
B |
C |
D |
E |
F |
G |
H |
I |
J |
K |
L |
M |
N |
O |
P |
Q |
R |
S |
T |
U |
V |
W |
X |
Y |
Z
Anchored Veneer
Anchored means fastened to the structure so that it can not fall off.
Anchoring Ties
A device such as a metal rod, wire, or strap used to attach one object (such as a layer of brick) to another object (such as the structure).
Ash mortar
In Los Angeles up until around 1939 Ash Mortar consisted of sand, lime and ash.
Baluster
A short pillar forming part of a series supporting a rail.
Balustrades
An entire railing system (as along the edge of a balcony) including a top rail and its balusters, and sometimes a bottom rail.
Black Paper
Stiff paper treated with a petroleum product to make the paper able to resist water. The paper is usually black so the construction industry has named it simply “black paper”. Black paper is what is usually used under the stucco or bricks to ensure water that soaks through the stucco or bricks does not enter the building. It is only water resistant because on a vertical surface the water does not spend much time against the paper (as it is running down the wall) so it does not have a chance to soak in.
Bond Beam
A continuous beam (or thickness) usually constructed of concrete and reinforced with steel rods on top of supporting walls. The purpose of the bond beam is to tie the walls together and distribute weight evenly to the walls below.
Chase
A continuous enclosure in a building that acts as a housing for such things as pipe, wiring (as in a chimney), or heating ducts. When you look at a house and you see the chimney sticking up past the roof you are looking at a chase unless the chimney is made of solid masonry. If it is solid masonry we call it the “stack”.
Chimney cap
Cap surrounding the top of the chimney brick and protects the masonry from the elements.
Copper flashings
Flashings made from the metal copper. Copper flashings are superior because they will never rust or rot away. In time the copper takes on a patina giving it an attractive look.
Corbel
A layer (or course) of bricks or other type of masonry units that protrude out from the layer (or course) below. The purpose of the corbelling is usually decorative although it is commonly used to form a ledge to support something.
Cricket
A structure usually made of sheet metal, placed behind another structure (such as a chimney) that protrudes up through the roof. The purpose is to divert water to each side of the protruding structure. The cricket prevents water from sitting directly behind the protruding structure.
Damper
A valve, usually a moveable or rotate-able plate, for controlling the flow of air or smoke and draft.
Drafting ratios
In fireplace laymen’s terms, drafting means the same as draw, which is how well the system takes the products of combustion from the fireplace up through the chimney to the outside. If a fireplace does not draft well, or draw well, you would get smoke in the room. The smoke would come out of the fireplace opening.
A drafting ratio is the size of the fireplace opening compared to the size of the flue. In order for a fireplace and chimney system to draft or draw well this size relation has to be correct. For example, if the fireplace was very big and the flue was small, the system would allow smoke to enter in the room.
Efflorescence
Comes to us from chemistry, and means loss of water from crystal. When a crystalline substance loses water a deposit is left and this process and the actual deposit is called efflorescence. It is harmless and is formed from a mineral which is basically a water soluble salt. It will wash away with special detergents and will stop appearing once the source of water is removed.
Fire Box
The combustion area of a fireplace, furnace or boiler, where the fire is contained.
Fire Chamber
See Fire Box
Fire Guard
A high tech cement like chemical compound that is not adversely affected by high temperatures and has a tremendous ability to stick to other masonry surfaces. Used inside of chimneys to seal cracks and to coat concrete that is adversely affected by high temperatures.
Flashing
A thin impervious material (such as metal) placed in construction (e.g., in mortar joints and through air spaces in masonry) to prevent water penetration and/or provide water drainage, esp. between a roof and wall, and over exterior door openings and windows. The copper seen in the photo below is the flashing. In the photo below the flashing prevents water from entering the building between the chimney and the roof.
Isokern
Modular masonry fireplace and chimney systems made from volcanic pumice stone used for indoor, outdoor, multifamily and commercial projects.
Load Bearing
Capable of supporting a load in addition to its own weight.
Level I
Home Inspectors, as thorough and as diligent as they are, perform what is known as a Level 1 Chimney Inspection when inspecting a home. To avoid undue technical jargon, a Level 1 Inspection is a cursory inspection of the chimney using only the naked eye. Are there any major signs of damage?, etc.
Level II
Of course a Level II inspection includes all aspects of a Level I inspection with the following points added:
|
1.
|
Has the chimney been constructed properly?
|
|
2.
|
All accessible portions of the chimney are inspected including all enclosed flues.
|
|
3.
|
Does the chimney show proper clearance from combustibles in accessible locations?
|
|
4.
|
All accessible portions of the chimney exterior and interior are inspected including areas with accessible attics, crawl spaces and basements.
|
|
5.
|
Shall include video scanning or other means of inspection.
|
Members
Any essential part as a post or beam, etc., of a framed structure. A structural member is any one piece of the framework that actually carries a load or helps another piece carry a load. In the human body your thigh bone is a structural member.
Modified Bituthene
A petroleum based product that looks and behaves like a sheet of rubber. Used to waterproof a wall when one really wants to ensure the wall does not leak.
Non Load Bearing
Only capable of supporting its own weight.
Portland Cement
Portland cement is the most common type of cement in general usage, as it is a basic ingredient of today’s concrete, mortar and plaster. The city sidewalks and curbs are one example of Portland Cement concrete. It consists of a mixture of oxides of calcium, silicon and aluminum. Portland cement and similar materials are made by heating limestone (as source of calcium) with clay or sand (as source of silicon) and grinding the product (clinker), with a source of sulfate (most commonly gypsum). The resulting powder, when mixed with water, will become a hydrated solid over time.
Portland cement was first manufactured in Britain in the early part of the 19th century, and its name is derived from its similarity to Portland Stone, a type of building stone that was quarried on the Isle of Portland in Dorset, England. The patent for Portland cement was issued to Joseph Aspdin, a British bricklayer, in 1824.
In terms of chimneys in Los Angeles, the use of Portland cement in mortar started after the Long Beach Earthquake (http://nisee.berkeley.edu/long_beach/long_beach.html) when engineers realized that seismic activity demanded the powerful bonding strength of Portland cement. Since Los Angeles did not experiance the Freeze — thaw cycle of the colder climates there were no disadvantages of using Portland Cement in the brick mortar in Los Angeles and it is standard practice today.
Powder coat
Powder coating is an advanced method of applying a decorative and protective finish to a wide range of materials. The powder used for the process is a mixture of finely ground particles of pigment (color) and resin, which is sprayed onto a surface to be coated. The charged powder particles adhere to the electrically grounded surfaces until heated and fused into a smooth coating in a curing oven. The result is a uniform, durable, high-quality and attractive finish.
Quoins
A right angle stone in the corner of a masonry wall to tie in or strengthen the wall. Seen in the corner and is usually distinguished decoratively from adjacent masonry. Original purpose was to reinforce an external corner or edge of a wall but today quoins are mostly decorative in nature and have no structural factors, being made mostly of either light weight precast concrete or expanded foam.
Rain caps
Some chimneys for heating systems, and for fireplaces, are equipped with rain caps to keep rain water from entering the chimney flue. Look for a flat or curved plate at the very top of the chimney. The rain cap can be viewed from the ground.
It is important for the home owner to periodically verify the integrity of the rain cap, especially after heavy rains and winds because weakened rain caps can often fail under these conditions. If a rain cap becomes dislodged, rain water can enter the flue and then run down into the heating system, or fireplace, and cause damage or system mal-function.
Smoke Chamber
The transition zone between a fireplace throat and fireplace chimney, extending from the damper or throat to the base of the first flue.
Smoke Shelf
The ledge directly behind the throat of the fireplace, at the base of the smoke chamber.
Sonotubes
A brand name for a cardboard pipe. The purpose of a cardboard pipe is to form round columns of concrete. One will pour concrete in the pipe and after the concrete has set — remove or cut away the cardboard pipe leaving the round concrete column. This cardboard pipe is treated so the concrete will not stick to it. Boston Brick & Stone uses Sonotubes to form round holes inside of solid concrete.
Spark Arrester
A noncombustible screen installed between the top of the chimney and the underside of the
chimney cap; prevents the escape of sparks and burning materials from the chimney.
Structural Members
Structural means having to do with support, in other words “holding something up. The skeleton provides the structural support for the human body. In a house the 2 x 4 wooded studs and beams provide the structural support thus are structural members. In a skyscraper the steel or concrete framework provides structural support and in all cases the structural support is what keeps the structure from falling to the ground.
Throat
The narrow passage above the fire chamber of a fireplace, forward of the smoke shelf and below the smoke chamber, generally has a damper which must be opened before the fireplace is used, and may be closed, when the fireplace is not in use.
Note: Dampers used with fireplaces that burn gas only must, by code, be in the locked-open position at all times.
Throat Mounted Damper
A damper located in the throat of a chimney.
Veneer
A brick or stone that is installed on the outside of a wall for decorative purposes only. The difference between a brick veneer wall and a brick wall is the brick veneer does not support anything and in fact must be at least partially supported by the structure. A brick wall supports loads such as the roof of the structure.
Wicking
In fireplace laymen’s terms it is the action of the chimney absorbing moisture from the ground surrounding it and continuing to absorb this moisture until in appears on the inside of the house. Because brick and concrete are porous they can both act much like sponges and “suck” water up out of the ground. The solution is always to eliminate the water in the ground surrounding the chimney.
Wythe (or withe)
Each continuous vertical section of wall, one masonry unit in thickness.
X-Bracing
Any system of bracing (bracing here means used to add strength) in which pieces of the framework are set to cross diagonally. When they intersect this way they form an “X”. This system makes a very strong structure.
