How Long Should It Take To Install 11 Replacement Windows
- How Long Should It Take To Install 11 Replacement Windows 2020
- How Long Should It Take To Install 11 Replacement Windows 10
- How Long Should It Take To Install 11 Replacement Windows For A
It typically takes about four to eight weeks from the time you place your order until your windows arrive (this can vary depending on the time of year and type of windows you order as well). On installation day, the time it takes to complete your project depends on the type and number of windows you’re installing.
$400 – $650 Per Vinyl Window
$700 – $1,000 Per Wood Window
$700 – $1,000 Per Wood Window
The average cost for a standard-size vinyl window that is double-hung, double-pane, and energy-efficient is between $400 and $650 per window installation. For a wood replacement window, expect to pay between $700 and $1,000 including installation. Get free estimates from window replacement companies near you.
Window Replacement Costs
Window replacement costs $550 on average with most homeowners spending between $400 and $1,000 per window including installation. The cost to replace every window in a 3-bedroom house ranges from $4,500 to $9,600 depending on the sizes, frame materials, type, and the number of windows. Labor cost for professional installation is $159 to $258 on average.
| National Average Cost | $550 |
| Minimum Cost | $200 |
| Maximum Cost | $2,000 |
| Average Range | $400to$800 |
Table Of Contents
Replacement Window Prices By Material
The average cost for a standard-size vinyl window that is double-hung, double-pane, and energy-efficient is between $400 and $650 per window installation. For a wood replacement window, expect to pay between $700 and $1,000 including installation.
Here are the average replacement window prices by frame material:
| Frame Type | Average Cost |
|---|---|
| Vinyl | $100 – $850 |
| Composite | $280 – $900 |
| Wood | $200 – $1,000 |
| Aluminum | $80 – $1,400 |
| Fiberglass | $150 – $1,400 |
| Clad | $300 – $2,000 |
Vinyl Window Replacement Cost
Vinyl window replacement costs range from $100 to $850 each with most homeowners paying between $400 and $600 for a double-hung, double-pane, and energy-efficient window. Vinyl frames are the most cost-effective type of window frame and require little maintenance, but over time the color may fade.
Replacement Wooden Windows Cost
For a wood replacement window, expect to pay between $200 and $1,000, or $700 on average including installation. Wood frames can contract or swell because of the exterior elements, and they need maintenance to keep them in tiptop shape, but they do provide excellent temperature insulation.
Composite Replacement Windows Cost
Composite window frames are more expensive than vinyl and cheaper than wood frames, costing $280 to $900 each. They also have better structural integrity than wood and vinyl and can be painted.
Aluminum Windows Cost
Replacement aluminum windows range from $80 to $1,400 each depending on the size, and number of panes. Aluminum window frames, being made from metal, are very durable and robust, low-maintenance, and more affordable when compared to wood. However, they also conduct more heat and cold than wood.
Clad Windows Cost
Clad window frames are the most expensive option for window frames at $300 to $2,000 each. With a vinyl shell over a wood or aluminum frame, they are low-maintenance. With the wood interior frame option, there is also more efficiency in energy reduction, because less heat or cold will pass from the outside.
Fiberglass Windows Cost
Fiberglass windows cost $150 to $1,400 each and are able to endure extremes in both hot and cold temperatures. Fiberglass windows are energy efficient and can offer the look of painted wood without the maintenance associated with wood windows.
Window Replacement Cost Calculator
The main factors used when calculating prices are the window type, the window framing material, and labor costs. The average cost for a typical low-E glass vinyl window is $244 to $373 while labor runs $159 to $258 to install. There are over 10 different window designs ranging from fixed non-opening windows to more efficient sliding and double-hung types.
Cost Of Windows By Type
A typical single-hung window replacement starts at $200, while a large double- or triple-pane bay window could cost up to $8,000 to install. Here are the average cost of windows for materials and installation:
| Window Type | Window-Only Cost | Window + Installation Cost |
|---|---|---|
| Basement Hopper | $60 – $370 | $180 – $500 |
| Single Hung | $100 – $500 | $200 – $600 |
| Double Hung | $150 – $600 | $250 – $800 |
| Fixed & Picture | $80 – $500 | $180 – $1,000 |
| Sliding | $150 – $600 | $250 – $1,000 |
| Basement | $50 – $500 | $200 – $1,000 |
| Storm | $150 – $750 | $250 – $1,100 |
| Glass Block | $80 – $800 | $200 – $1,200 |
| Casement | $200 – $1,000 | $350 – $1,500 |
| Tilt Out | $350 – $1,500 | $500 – $2,100 |
| Double Pane | $60 – $2,800 | $120 – $3,800 |
| Custom | $300 – $3,000 | $500 – $5,000 |
| Egress | $500 – $2,500 | $2,000 – $5,000 |
| Folding | $1,500 – $4,800 | $2,500 – $5,600 |
| Bay | $500 – $2,500 | $1,500 – $8,000 |
| Bow | $1,500 – $5,000 | $2,500 – $10,000 |
Single-Hung Replacement Windows
A typical single-hung window costs $100 to $500 on average, and is one of the most popular choices due to price. A single-hung window keeps the top half of the window fixed in place and the bottom half of the window moves up and down.
Double-Hung Window Prices
A typical double-hung window costs on average $150 to $600. A double-hung window allows both the top and bottom halves to move up and down. If you opt for the more expensive version, the top and bottom halves also swing inward.
Picture Window Replacement Cost
Depending on the size, a fixed or picture window will cost $80 to $500, on average. Fixed windows only have one pane of glass and do not open. Picture windows often require custom sizing which can increase your cost.
Casement or Awning Window Prices
A typical casement window costs between $200 and $1,000, depending on the framing material. These windows open from left to right by using a hand crank, allowing a wide opening. Casement windows are often found near basements or ceilings. A casement style that's hinged to the top is called an awning window, while a hopper is hinged to the bottom.
Bay and Bow Window Costs
Both bay and bow windows start at around $500 and can go all the way to $10,000+. Both types extend outward from the wall and require framing, flashing, and roofing extras. Typically most homes will only have one or two bay windows on the front of the house, and possibly a third on the rear of the home facing into the backyard.
- Bay Window – Costing $500 to $2,500, a bay window is a series of three windows. Generally, there is a large window in the middle with a smaller window on each side, and it extends outward from the house.
- Bow Window – Costing $1,500 to $5,000, a bow window usually contains five or more individual windows that are placed in a curved setting.
Sliding Replacement Windows
Depending on the size, sliding windows typically cost around $150 to $600. These windows work just like single- or double-hung windows but move horizontally instead of vertically. They come in many different types and styles, allowing either one side or both sides of the window to move.
Basement Window Replacement Cost
Many basement windows are small and affordable. The average prices we see range from $50 to $500 per window. Typically, these will be fixed windows that do not open for maximum insulation.
Egress Windows Installation Cost
Egress windows vary quite a bit and can get expensive. You can expect to pay around $500 to $2,500 for an egress window. If you choose to place an egress window in a basement, you can expect to pay much more, with prices starting at $2,000 and going up to $5,000. An egress window is required by code if you plan to put a bedroom in the basement. These windows can also be used as an escape route during a fire or natural disaster.
Glass Block Windows Cost
The range of costs for glass block windows span from around $80 to $800, and the prices are generally dictated by the size of the window being installed or built. Extra features like constructing it on a curve will also add to the project cost. Glass block windows are often selected for bathrooms because of the privacy afforded by them.
Folding Windows Cost
Folding windows are not as common as traditional windows. Their product cost ranges from $1,500 to $4,800, but your overall project cost will rise well beyond that because of the install costs for this specialty upgrade, which rides in a trench in the sill to facilitate their opening and closing. These make an excellent choice of windows if you love having an unobstructed view.
Custom Replacement Windows Cost
Custom windows can get expensive but typically run from $300 to well over $3,000—just for the window and not including installation. Custom windows are typically only used when the window openings are an irregular size or not uniform as seen in very old homes. Your contractor will measure and order your custom windows directly from the manufacturer and then install them.
Average Cost To Replace Windows
The average cost to replace windows is between $400 to $800 per window with most homeowners spending around $550 each including installation. Given the average home will likely have around twenty windows, you can expect to pay about $8,000 to $12,000 to replace them all, and more if the window frame openings need any additional work or replacement.
Cost To Install Replacement Windows
The typical cost to install replacement windows is $403 to $631 per window which includes professional labor. You’ll pay more if your home is a two-story home, and more again if the windows are triple glazed or filled with argon gas. Replacing your windows will add an updated look to your home and should also pay you back in the form of reducing your energy costs.
Labor Cost to Install Replacement Windows
The labor cost to install a standard-size vinyl replacement window is between $159 and $258. Expect to pay about $35 to $80 to remove and replace single-pane window glass set in putty or vinyl stops, or $100 to $175 per double-pane window. Add another $170 per window to install weather stripping.
This should boil down to a labor cost of $35 to $65 per hour to install replacement windows. Anything other than a regular window can cost more to install, such as skylights, casement windows, bay windows, windows on the second or third story, etc. Removal of old windows and transporting them for disposal costs about $70 to $250 per window.
Home Windows Replacement Cost
Home windows replacement cost for an average 3-bedroom house with twenty windows ranges from $6,000 on the low-end to $16,000 on the high-end depending on the size, style, quality, and the number of windows. With an average of one window for every 100 square feet of a home, the following chart includes window installation costs for a range of house sizes, and for three different qualities of windows used.
| Home Size (SF) | # Of Windows | Lower End | Average | Higher End |
|---|---|---|---|---|
| 1,000 | 10 | $3,000 | $5,000 | $8,000 |
| 1,500 | 15 | $4,500 | $7,500 | $12,000 |
| 2,000 | 20 | $6,000 | $10,000 | $16,000 |
| 3,200 | 32 | $9,600 | $16,000 | $25,600 |
| 4,200 | 42 | $12,600 | $21,000 | $33,600 |
| 5,400 | 54 | $16,200 | $27,000 | $43,200 |
Window Replacement Cost Per Window
The average window replacement cost is between $400 and $1,000 per window with most homeowners spending $403 to $631 on average. A small single-hung window will start at $200 to install, while a wooden double-pane window runs from $700 and $1,000.
Window Replacement Cost by Room
Different windows have different prices because of the ease or difficulty of installation.
| Location | Average Cost |
|---|---|
| Basement Window | $200 – $1,000 |
| Basement Egress | $600 – $1,500 |
| Bathroom | $300 – $1,000 |
| Bedroom | $300 – $1,000 |
| Kitchen | $300 – $2,500 |
Cost of Replacing Windows by Size
Regardless of the frame type or opening mechanism, the lowest cost replacement project is where you have windows placed into an opening of the same size as the original window, without the need for any extra time and effort to create a larger opening. With so many options, styles, and sizes available, the best way to get an exact price is by contacting a window installer near you today. The most common window sizes are:
- Wood - 18 to 60” wide and 18” to 48: tall
- Vinyl - 18” to 48” wide and 18” to 36” tall
Single-Pane Window Replacement Cost
The average cost to replace a single-pane window is $288 to $460. These are the most basic windows with the least insulation that are typically found in older homes. Standard single-pane glass can be purchased for as little as $2.50 per square foot.
Double-Pane Window Replacement Cost
The average cost to replace a double-hung, double-pane window ranges from $450 to $1,000. A double-pane vinyl window ranges from $450 to $600 to install, while a double-pane wood replacement window costs between $800 and $1,000.
Window Cost if Frames Are Rotting
It’s much cheaper to just replace the glass in a window rather than the entire wood frame plus glass, which must be done if the frames are rotting or warping. The final price will be about double the cost of replacing the glass. See the difference in framing material costs in our comparison table above.
Cost to Replace Windows in an Old House
The average cost to replace windows in an old house is $800 to $3,000 per window which is double or triple standard pricing. Factors that affect your price include rotten wooden frames, the need for custom window sizes, the need to upgrade to current standards, and removing any counterweights. Depending on the current state of the home, you may be able to keep the current frame in place and just swap on the glass for an average cost of $350 per window.
Additional Factors
Other possible expenses you could incur as part of your window replacement are:
- Framing cost - $365 to $1,500
- Insulation cost - $200 to $600
- Cost to repair trim - $200 to $850
- Siding repairs cost - $200 to $1,200
- Cost to install drywall - $2.12 per square foot
Your window replacement contractor should be able to include the necessary additional expenses in his/her quote and will likely have the workers and tools required to do the job.
Full Frame Window Cost vs. Retrofit Replacement
The vast majority of windows are available as full-frame (new construction) or replacement windows. Replacement retrofit windows are available in custom sizes, whereas full frame windows are generally only available in standard sizes which are installed into an existing opening.
| Full-Frame Windows | Replacement Windows |
|---|---|
| Install is between $150 and $1,000 per window | Install is between $100 and $300 per window |
| Only available in standard sizes | Custom sizes available |
| Requires drywall removed to expose studs | Set into existing framing |
| 12.5% cheaper for windows, a lot more to install | 12.5% more for windows, a lot less to install |
| Needed if the frame is damaged or in remodeling | Good for replacement or updating home |
| Extra costs from an interior and exterior wall finish | No additional costs from stripping back walls |
Full-Frame Window Replacement Cost
A full-frame window is a new window in a frame with a sash. An installed full-frame window will cost $150 to $1,000 per window for professional installation and is only available in standard sizes.
The full frame option requires the wood that surrounds it to be nailed into the studs in the wall. The opening will have to be stripped down to the studs by cutting the drywall on the interior wall, replacing the studs around the window, and finishing out the drywall once the new window has been installed. In most cases, this will also require removing a portion of the siding on the exterior of the home, which will also need to be finished out when the window is in place; and if you have brick on the outside, your costs will go up significantly.
Cost To Install Retrofit Windows
A retrofit replacement window is a window that fits inside an existing frame in the home. A retrofit replacement window will cost $100 to $300 each and is much easier for a professional to install. Retrofit windows are an excellent choice when you're updating your home.
Energy-Efficient Window Replacements
Most Energy Star rated windows will carry a rating that indicates the rate of insulation performance (called the U-Factor, generally measuring between 0.30 and 0.60), and a rating to show how well the window blocks the heat of the sun (called the solar heat gain coefficient, which measures between 0.27 and 0.40).
There can be an effective reduction of heat loss of between 30% to 40% achieved by upgrading to products that carry an R-value of 5, and a U-factor in the region of 0.15. Energy.gov has a table which details the most efficient windows. However, the cost benefits may not be realized to where the savings cover the cost of the upgrade, because it could take between 18 to 20 years to break even.
According to EnergyStar, “Energy Star certified windows can lower your energy bill by an average of 12 percent. That’s about $27 to $111 per year for a 2,000-square-foot single-story home with storm windows or double-pane windows and $126 to $465 if your home has just single-pane windows.”
Energy-Efficient Windows Tax Credits
According to the US Department of Energy website EnergyStar, “Tax credits for residential energy efficiency have now expired. The tax credit for builders of energy efficient homes and tax deductions for energy efficient commercial buildings have also expired.”
Best Replacement Window Brands
According to the Consumer Reports window buying guide, the following is their list of top window manufacturers with some of the price ranges for products they offer:
| Brand | Cost | Features | Warranty |
|---|---|---|---|
| Andersen | $95 to $1,750 | Composite, clad, wood, and vinyl windows; Both low-E and argon-filled, high-efficiency in double-hung and casement styles | 20-year warranty on the glass; 10 years on the rest of the window |
| Marvin | $350 to $1,500 | Includes double-hung, single-hung, sliding (glider), casement, awning, bay, specialty, and round top windows | Glass for 10 years; Cladding finish free from defects for 20 years; Warrantied against coastal corrosion for 10 years |
| Jeld-Wen | $95 to $1,100 | Clad-wood, custom wood, premium Atlantic vinyl, premium aluminum; Styles: double-hung, single-hung, fixed, sliding, casement; Impact-resistant glass; Resin system Kynar 500, which prevents the window structure from fading or chalking | Ownership lifetime on the vinyl; 20 years on the wood and clad products; 10 years on aluminum; Certified to meet code in areas with frequent hurricanes |
| Kolbe | $250 to $950 | Stock and made to order; Include styles like casement, awning, double-hung, sliding, and specialty windows in wood and aluminum clad | Between 10 and 20 years |
| Pella | $120 to $1,800 | Wood, clad, vinyl, and aluminum construction; Stock sizes and custom windows | Limited lifetime warranty coverage |
| Ply Gem | $49 to $180 | Vinyl construction; Available as both low-E and argon-filled glass options | Limited lifetime warranty coverage |
| Reliabilt | $75 to $290 | Vinyl construction; Includes double-hung as well as casement windows and in both low-E and argon-filled glass; Standard sizes and extensive options for custom orders | Limited lifetime warranty coverage |
| Simonton | $137 to $460 | Includes low-E and argon-filled double and single-hung, slider, casement, awning, bay and bow, picture, geometric and garden windows; Stock sizes and custom windows | Limited lifetime warranty; Transferable if you purchase a home that already has Simonton windows or doors installed |
| Weather Shield | $250 to $1,200 | Low-E and argon-filled double-hung, slider, casement, awning, and special shape windows; Stock sizes and custom windows; Historic and hurricane windows | Free from defects in material or workmanship for 20 years |
Window Warranty
A good window warranty includes coverage for components, performance mechanisms, and more including:
- Pieces, parts, and materials
- Glass systems and frame
- All locks and hardware
- All installation and labor
- 100% non-pro-rated
- 100% transferable
Frequently Asked Questions
How Much is Window Glass Replacement?
Window glass replacement costs$150 to $500 on average, depending on the size and type. Installers charge $35 to $75 per hour, and the glass itself costs $30 to $100. These costs will rise if argon gas has to be injected between the glass, and even more if the seals need to be replaced.
Are Replacement Windows Worth The Cost?
Replacement windows are worth the cost if your future energy savings are high, you will remain in the home for about 20 years, or if having newer, more energy efficient windows will help sell your home faster. In most cases, homeowners will see a 70% return on investment for the project costs upon the sale of a house with upgraded windows.
How Often Should You Replace Windows?
Manufacturers tend to agree on the need to replace windows after about 20 years, especially older windows. Today, windows are warrantied anywhere from 5 to 20 years, and some are even covered for as long as you own the home. The following is an additional set of criteria you could consider.
- Poor window insulation, which increases energy bills
- Poor sound insulation
- Failing opening mechanisms
- Warping or rotting window frames
- Ugly windows won’t sell a home well - recoup a return of around 70% on the sale with new windows
- Foggy double-paned windows
How Can I Get The Lowest Cost On Window Replacements?
The lowest cost window will likely provide the least insulation, but keep in mind that you can save by
- Installing fixed or picture windows
- Installing one big window rather than multiple smaller windows
- Installing in the offseason
- Using builder grade or contractor grade windows rather than architectural grade
- Using standard sizes and shapes over custom products
- Not sourcing windows from a dealer that only stocks one brand
How Much Does A Mobile Home Replacement Window Cost?
A mobile home replacement window costs as high as $300 from some vendors. Home Depot offers Tafco mobile home windows priced between $61 and $154 each.
How Much Is A Condo Window Replacement?
Some condo HOAs have specific rules on the look and type of windows allowed in the home. The costs for most windows in average-priced condos will average somewhere around $500, and more for higher-end condos.
What Is The Cost Of Replacing Windows And Frames?
Expect to pay an additional 50% to 100% if the frames need to be replaced before new windows are installed. Generally, unless the home is really old with original windows, the damage is often localized to one side of the house, so not every window will incur the extra cost.
How Much Is It To Swap Out Windows And Doors Together?
The bigger the spend with a contractor, the higher the likelihood there is for discounts. The caveat to looking for a lower cost from a package deal is that you are restricted by the types of product that vendor carries, and you could end up with windows you love and doors you are less keen on.
How Much Does Window Disposal Cost?
In the bid from your contractor, you may see a line item for old window disposal with costs ranging from $50 to $80 per cubic yard as well as a $30 to $40 per hour charge to load up a trailer with the materials and drive it to the appropriate dump.
DIY Vs. Hiring a Pro
Replacing the windows in your home is not a project for the faint of heart, and even more daunting of a task if you have a two-story house. There are many different possible failure points where you could easily end up with having invested many frustrating weekends. In the worst-case scenario, you need a professional to come to your home to redo the installation. When you hire the right professionals to do the work, it will be done fast and flawlessly.
Why Hire a Professional?
The task of replacing the windows in your home is not as straightforward as it may appear in a YouTube video. Advantages of hiring professional window installer include:
- Excellent work – This is a craft that the professionals you hire have spent years learning and perfecting. Each window will be installed with no gaps left for heat transfer to keep the climate in your home just the way you want it.
- Equipment and tools – Professional window installers will have all the tools required to install your windows.
- Better prices – Professional installers typically have access to better materials and better prices than a member of the public.
- Faster – Professional window installers will be 8 to 10 times faster than the average homeowner who has decided to do the work themselves.
- Cleanup – When the last window has been installed, and everything looks perfect, your installation team will load up the original windows and cart them off to be disposed of properly.
- Issues – In addition to being able to measure everything accurately before any windows are ordered, they will also know how to deal with situations like rotting wood, and mold, as well as do the work, so it complies with any city ordinances, HOA rules, or building codes specific to your area.
Getting a Professional Window Replacement Quote
As with any home improvement project, get between 3 to 5 cost estimates after you research potential contractors to do the work. You should see very similar elements on quotes from top professionals, and those elements include the following:
How Long Should It Take To Install 11 Replacement Windows 2020
- Before Installation – Any design costs or setup costs.
- During Installation – Specific costs associated with each window and expenses for any potential issues they might incur once the studs are exposed—like dealing with mold, rotten or damaged structural elements, and any costs related to insulation or weatherproofing.
- After Installation – The costs associated with removing the old windows and any construction debris and their proper disposal.
Along with the quotes from each potential contractor, you can ask for an electronic or paper copy of the guarantee the windows and the installation come with.
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Step 1: Measure the Window Opening
The rough opening must be plum, level, square and ½-inch larger than the window size in width and height, not including the nailing fins (See fig. 1).
Close and lock the sash (the frame that holds the glass) to keep the window square during installation.
How Long Should It Take To Install 11 Replacement Windows 10
Step 2: Install the Flashing
Use self-adhesive flexible flashing a minimum of 4' wide, which has a self-adhering surface on one side. It should be approved for use on vinyl, wood and other substances such as house wrap. This flashing material must meet a minimum water resistance of 24 hours in accordance with ASTM-D779.
Sill flashing should already be applied before window installation and it should extend beyond the sides of the window nailing fin at least two inches. (See fig. 3)
Apply jamb flashing over the jamb-nailing fin, continuing over and beyond the sill flashing, two inches below. Apply the head flashing similarly, extending two inches past either side of the jamb flashing, to complete the window flashing detail.
How Long Should It Take To Install 11 Replacement Windows For A
Install batt insulation between the window and rough opening. It is very important that these openings are not over-stuffed because they can warp the frame. Do NOT use expanding foam. Doing so will void warranties.
Step 3: Caulk the Window
Apply a 3/8-inch continuous bead of silicone caulking to the interior surface of the nailing fin, covering the holes in the fin, to seal the window's fin to the sheathing or house wrap.
If the rough opening is larger than the window by more than ½-inch, also apply the caulk to the sheathing or house wrap, making sure the bead is no more than ¼-inch from the edge of the rough opening. It should be covered by the nailing fin when the window is installed.
Step 4: Set the Shims
To keep the window straight and level, install shims at all locations where the jamb, intermediate jamb, or the stiles of a slider meet the sill. (See fig. 2A & 2B)
Evenly place ¼-inch shims on the sill plate of the window opening. Double or triple windows should have a shim under each mullion (the vertical bars between the panes of glass), intermediate jamb or the center stiles of sliders. (See fig. 2A & 2B)
Step 5: Set the Window
Set the window on the shims and adjust the side clearance to be equal on both sides. Tack one upper corner of the nailing fin to keep the window in place. Check the sill with a level and adjust the shims as required to level the sill. Re-adjust the side clearance if necessary.
Shims must be cut to exact thickness to fit snug and not fall out. Do not force the shims into place, because this can push the sill out of level. Shim both sides of the window as needed to assure the window is plumb and the margins are equal. (see fig. 2A & 2B)
Measure the window diagonally, from bottom left corner to top right corner and from bottom right corner to top left corner to ensure it is square.
When the above is done correctly the width across the top, middle and bottom of the window will measure the same. The wool pile clearance between the sash stile and jamb mainframe should be equal. The meeting rail and lock rail should align evenly, with parallel sight lines. The window locks should engage smoothly.
Step 6: Nail the Window Fins
Use stainless or galvanized steel roofing nails, a minimum of one inch, or long enough to penetrate studs.
Nail the entire perimeter of the nailing fin to the sheathing, using every other slotted hole at a minimum on single windows. Nail double and triple windows in every slotted hole.
Nail the fin snug but do not 'sink' the nails. Nailing should be just tight enough to hold the window but not stop the movement of the framework underneath during expansion and contraction. Make sure the head and sill are not crowned up or down, or the jambs bowed in or out.