Start by Confirming the Installation Type

Gentek identifies the Model 1100 as a new construction sliding patio door. Its fusion-welded frame includes an integral nail flange intended to be fastened and flashed as part of the exterior wall assembly.

That distinction matters. A new construction door is generally appropriate when the framing, sheathing, water-resistive barrier, and flashing area around the opening are accessible. Typical applications include new homes, additions, newly framed openings, and some full-frame remodeling projects.

An insert replacement normally leaves the old frame or portions of the existing opening in place. That may not provide the access needed to use the Model 1100 nail flange correctly. Contractors should determine the installation method before measuring or quoting the door.

Review the product through Suburban Wholesale & Supply’s Gentek 1100 Series patio door page .

Rough Opening, Unit Size, and Daylight Opening Are Different

These measurements should never be treated as interchangeable. A nominally described six-foot patio door does not necessarily provide a six-foot frame, glass area, or clear passage. Consult current Gentek documents for the exact unit and rough-opening dimensions of the configuration being ordered.

How to Document the Rough Opening

Measure the prepared structural opening rather than relying on plans, an old invoice, or the nominal size of the existing door. Framing can change during construction, and older openings are not always square or built to current nominal dimensions.

1. Measure the width at the top, middle, and bottom. Record all three measurements instead of keeping only the largest one. Differences can reveal bowed or out-of-plumb jambs.
2. Measure the height at the left, center, and right. Record from the structural sill surface to the structural header. Do not measure from removable flooring or an unfinished trim piece unless the final relationship has been established.
3. Check both diagonals. Equal diagonal measurements help indicate a square opening. Diagonal measurements alone do not prove that the sill is level or the jambs are plumb.
4. Check the sill for level. A sloped, crowned, twisted, or sagging sill can distort the door and interfere with panel operation.
5. Check the jambs for plumb. An opening can have correct width measurements and still lean to one side.
6. Measure the wall depth. Include the framing, sheathing, interior finish, exterior cladding, and any extension jambs or trim required to complete the opening.

Inspect the Sill Before Ordering

The sill carries the weight of the patio door and its glass. It must provide the continuous, stable support required by the manufacturer. An unsupported section, raised fastener, deteriorated framing member, uneven masonry surface, or poorly planned flooring transition can create installation and operating problems.

Determine whether damaged framing must be replaced and whether the opening requires a sill pan, flashing membrane, formed pan, end dams, or another approved water-management detail. Those decisions can affect the opening dimensions and should not be postponed until the door is standing at the jobsite.

Conditions to document

• Wood framing, concrete, masonry, or another sill substrate
• Signs of decay, corrosion, staining, leakage, or insect damage
• Interior finished-floor height and exterior deck, patio, or landing height
• Drainage direction and exposure to wind-driven rain
• Required threshold and accessibility conditions
• Available space for sill flashing and perimeter sealant joints
• Existing utilities, radiant flooring, wiring, or other concealed conditions

A level patio, deck, or concrete slab outside the door should not be assumed to provide drainage. The complete transition must be evaluated so water is directed away from the opening rather than trapped against the threshold.

Confirm the Door’s Operating Direction

Handing terminology can be misunderstood because one person may describe the door from the interior while another describes it from the exterior. Avoid relying on “left-hand” or “right-hand” alone.

State the viewing position and identify which panel moves. A marked drawing should show the interior, exterior, fixed panel, operating panel, handle, lock, screen, and direction of travel.

Gentek describes the Model 1100 as field-reversible, but its published product information limits that feature to the 80-inch door height. Confirm the exact configuration and current instructions instead of assuming that every Model 1100 can be reversed after delivery.

Verify the Available Model 1100 Configuration

Gentek currently lists the Model 1100 as a two-lite sliding patio door available in 5-foot and 6-foot widths. A project requiring a three-panel or four-panel configuration, a larger opening, or a different architectural style should be compared with another patio-door product.

Do not alter the wall opening simply to accommodate a preferred nominal size until the header, load path, structural requirements, exterior cladding, interior finish, and applicable permits have been evaluated. Changing the opening can become a structural project rather than a routine door installation.

Suburban Wholesale can help contractors compare the Model 1100 with other products in its Gentek patio-door selection .

Select the Glass Package Using Project Requirements

Gentek identifies the BarrierXP insulating glass package as combining Low-E glass, argon gas, and a Super Spacer structural foam spacer. These components can contribute to thermal performance, but the correct package depends on climate, orientation, shading, code requirements, and the exact door configuration.

Ask for the performance documentation associated with the ordered unit. The National Fenestration Rating Council values may include U-factor, Solar Heat Gain Coefficient, Visible Transmittance, and other applicable ratings. Do not use numbers from a different size, glass package, or configuration as though they automatically apply.

Glass questions to answer

• Which direction does the door face?
• Is it shaded by an overhang, porch, trees, or neighboring structure?
• Does the applicable energy code require a maximum U-factor or SHGC?
• Is safety glazing required for the selected location and configuration?
• Does the project have noise-control or privacy concerns?
• Will grids be placed inside the insulating glass unit?
• Does the project elevation require capillary-tube considerations?

Gentek notes that insulating-glass units requiring capillary tubes may experience some argon depletion. Confirm elevation and shipping requirements before finalizing the glass package.

Document Colors and Grid Selections

Gentek currently lists White, Beige, and Classic Clay as Model 1100 interior colors. Its published exterior choices include White, Beige, Classic Clay, Black, Architectural Bronze, American Terra, Hudson Kaki, Desert Clay, Sand Dune, English Red, Storm, and Castle Gray.

Current grid patterns include Colonial, Single Prairie, and Craftsman, with published 5/8-inch flat, 3/4-inch contoured, and 1-inch contoured profiles. Availability should be confirmed for the exact door configuration.

Record the interior and exterior selections separately. “Black patio door” does not establish whether the customer expects black on both sides, black only outside, or coordinating black hardware.

Check the AAMA Gold Label Information

The AAMA Gold Label Certification Program is administered by the Fenestration and Glazing Industry Alliance. The program provides a method for identifying qualifying fenestration products produced under a certification system that includes laboratory testing, manufacturing-site inspections, and ongoing program requirements.

The label is not a substitute for reading its information. Confirm that the product designation, tested size, performance class, performance grade, referenced standard, and other listed details correspond with the project requirements.

Product certification and installation quality are separate issues. A certified door can still underperform if it is installed in an unsuitable opening or if the sill, flashing, fasteners, shims, sealants, and drainage details are mishandled.

Apply InstallationMasters Principles

FGIA’s InstallationMasters program provides professional education and certification related to installing windows and exterior glass doors. It emphasizes evaluation of the opening, water management, material compatibility, manufacturer instructions, and correct installation practices.

InstallationMasters training does not replace Gentek’s instructions, applicable codes, project specifications, or engineering. It reinforces an essential principle: the door and wall must function as an integrated system.

Installation details to establish before delivery

• Approved sill-pan or sill-flashing method
• Flashing sequence at the sill, jambs, and head
• Connection to the water-resistive barrier
• Compatible sealants, membranes, backer rods, and primers
• Correct fastener type, length, placement, and substrate
• Shimming and frame-anchoring requirements
• Perimeter insulation that will not distort the frame
• Exterior drainage and weep-path protection
• Interior and exterior trim transitions

The Final Ordering Checklist

Popular Homeowner Questions