Facilities management paper
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ZemkeCh16PPT.pptxThe Building’s Structural Components
Chapter 16
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This chapter will focus on:
Foundations
Framing
Exterior finishes
Insulation
Windows
Roofs
…or how the building is put together
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Foundations
Buildings are heavy, and perhaps tall
The weight and movement of the building needs to be anchored to a secure surface below ground
A building’s foundation gathers the weight and movement of the building, then transfers it to a stable sub-strate (layer) of material below ground
Prevents the building from:
Sinking
Tipping over
Twisting
Collapsing
Breaking
Sliding away
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What kind of soil is on-site?
Sandy
Clay
Rock or other mineral deposits
Bedrock
Loam
Ideally, you should be able to rest the building’s foundation on bedrock or very stable clay
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Types of foundations
Shallow foundations (e.g., mat, slab, or raft)
These are literally like a raft that floats in the pool. The building rests on the slab, which rests on top of the ground (or just below the surface).
Good for low-rise and lightweight buildings
Deep foundations
The building will sit on a slab, but the slab will be supported below by pilings or piers that go deep into the soil to rest on the stable substrate
Suitable for tall buildings and/or heavy buildings
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Slab/mat/raft foundation
Deep foundation
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Building “loads”
We use the word “load” in a lot of different ways in facilities management
Here, it refers to the combined weight and movement of the building and its occupants
Four types of loads:
Static (dead) load
Dynamic (live) load
Seismic load
Shear load
The weight and kinetic energy of the movement of the weight needs to be transferred to the foundation (and then down to the stable substrate)
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Framing and walls
Framing collects the weight and movement (loads) of the building, then transfers it down to the foundation
Framing materials include:
Wood
Structural steel
Concrete masonry unit (CMU)
Poured concrete with steel reinforcement
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What is concrete?
Artificial stone, made of:
Portland cement
Aggregate
Water
Interesting note:
Concrete does not dry – it cures
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Concrete has high compressive strength, but weak tensile strength
Can bear very heavy weights, but…
Requires reinforcement so that it does not snap in half
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Concrete (cont.)
Poured-in-place concrete is mixed and poured on-site into forms
Pre-cast concrete can be made in a factory and then transported to the job site
Reduces the installation time
May improve the quality of the concrete, since it is made under factory conditions
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Now that we have a foundation and a frame for the building, it’s time to close the building’s sides
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Exterior finishes
Once we have a frame, we close the “box” by attaching siding, such as plywood or oriented strandboard (OSB)
We can then attach the exterior finish of the building
First, we’ll look at applied siding, which is attached to the exterior
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Siding
Wood – very traditional material
Long strips (clapboards) or shingles or shakes are nailed to the framing
Advantages and disadvantages?
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Vinyl siding – mimics the appearance of wood, but at a much lower cost
Advantages and disadvantages?
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Fiber-cement board
A paste of fibers and cement is mixed and formed into boards, strips, shingles, or other shapes
Mimics the appearance of other materials
Advantages and disadvantages?
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Brick
Traditionally, brick served as both the framing and the exterior finish
It is heavy and expensive
Today, we close the box of the building and then attach a thin layer (“veneer”) of brick as a functional, decorative, non-load bearing finish
Brick requires mortar, which can deteriorate over time
Mortar occasionally requires tuck-pointing
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Shingles and shakes
These are slabs of wood that are attached to the building’s sides
Usually made of a wood that is weather and insect resistance, such as cedar or redwood
Sometimes provides an attractive haven for insects
They might not destroy the wood, but they might annoy your employees and guests!
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Glass
Glass-sided buildings are relatively lightweight, which permits us to build very tall buildings
The steel frame is constructed, then specially-designed glass window panels are hung on the outside of the frame
Advantages and disadvantages?
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Stucco and EIFS
Stucco is a traditional material made of mud or cement; it is spread on top of the building’s “box”
Traditional stucco materials are fragile and chip easily. They are also susceptible to water damage and deterioration from freeze/thaw cycles
Exterior Finishing and Insulating System (EIFS) is a modern version of stucco
Less fragile and more resistant to water damage
Comes in a wide variety of color
Very common building finish in the south and southwestern US
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Stucco
EIFS
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Other exterior finishes
Stone
Poured concrete
Metal panels
Numerous other options!
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Insulation
The purpose of insulation is to inhibit heat energy transfer
We measure a material’s ability to inhibit heat energy transfer by determining the material’s R-value
Some materials are more resistant to heat transfer; these materials are rated as having a higher R-value
Calculating a wall assembly’s R-value is like adding up how many calories are in a sandwich
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R-value
Each material has an R-value
These can be found online, (look for information published by ASHRAE)
You will either see the R-value listed “for thickness listed” or as an R-value “per inch thickness” (or per centimeter)
Find the R-value for each material in the wall assembly, then add them together to find the wall’s R-value
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R-Value Example
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R-Value Example
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R-Value Calculation
Starting from the outside: R-Value
Brick 0.48
Building paper (Tyvek) 0.00
Sheathing 0.77
Studs (framing) 0.00
Insulation 15.00
Vapor barrier 0.00
Drywall/gypsum board 0.45
Total 16.70
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R-value calculations
Once you have found the wall’s R-value, you can compare it to the recommended R-value for your area
If the R-value is lower than recommended, you can add insulation to improve energy efficiency
You’ll see that some materials have an R-value of zero. These materials perform some other function in the wall, but they do not provide insulation
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Windows and doors
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How are windows made?
Frame + glass
Single-pane (single-glazed)
Dual-pane (double-glazed)
Triple pane (triple-glazed)
For double and triple-glazed windows:
The panes of glass are separated by spaces that are vacuums. This space is called a thermal break, which provides the insulating function.
Low-emissivity (low-e) windows also provide a reflective film and inert gas to increase the insulating power
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Strangely…
The insulating value for a window is expressed as its U-value, rather than an R-value
The U-value is the inverse of the R-value
Therefore, a lower U-value and a higher R-value are desirable
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Window safety
Many hospitality properties (particularly hotels) now have windows that do not open
More energy efficient
Less likely to have people go out the window
However, if your property’s windows do open, you should install window guards and hardware that restricts how far the windows will open
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Doors
Doors and door frames in commercial facilities are often fire-rated
The fire-rating specifies how long the door and frame will remain intact if a fire is raging next to the door assembly
30-minutes, 45-minutes, and 60-minutes are typical
Do not drill into or otherwise tamper with these doors, or you will destroy their fire rating
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Roofs
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Roof components
Roofs play an important role in repelling solar heat transfer, weather, wind, and other forces
All roofs have a frame, decking, waterproofing layers, then a final finish
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Sloped roofs
Sloped roofs permit water to roll off of them easily
Common sloped roof finishes include:
Tile
Asphalt shingle
Wood shingle or shakes
Slate
Metal
Advantages and disadvantages?
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While water rolls off a sloped roof…
It falls straight down to the ground next to the building
The water can infiltrate the foundation, wick up the walls, and create a wet interior wall (with mold)
Install gutters with downspouts that direct the water downhill and away from the building
Gutters need to be cleaned, which no one likes to do
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Snow may collect on the roof; if it is very heavy and very deep, you may need to shovel your roof to prevent collapse!
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Flat roofs
Flat roofs aren’t really flat – they have a slight slope to direct rainwater and snowmelt to drains that are located at the edges of the roof
The drains direct the water down to the ground, then out to the yard (preferably downhill, to prevent infiltration)
The drain openings need to be free of dirt and debris, so that water flows freely
If not, pools will form on you roof, which will lead to leaks and, potentially, collapse
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Caution
Flat roofing materials are fragile and will crack or puncture if you walk on them
If there is a path, do not leave the path!
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Current trend: white roofs
Lighter colored roofs reflect more solar heat than do darker roofs
A current trend is to install a white roof, which can save as much as 40% on your cooling costs
However…a lot of building managers forget that roofs get dirty. A dirty white roof will rapidly lose its energy efficiency, so you will have to keep that roof clean!
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Another trend: “green” roofs
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Current construction projects
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