House Wrap & Vapor Barrier Installation
in Apex, NC
Apex Pro Siding & Wrap brings over 15 years of hands-on experience in siding, house wrapping, and exterior insulation systems. House wrap is not an accessory or an upgrade — it is a code-required component of every exterior wall assembly in North Carolina. The NC Residential Building Code, Section R703.2, mandates a weather-resistive barrier on all exterior walls beneath siding, regardless of siding material. Its function is specific: block liquid water that penetrates the siding layer from reaching the sheathing and framing, while remaining permeable enough to allow water vapor to escape outward from the wall cavity. A house wrap that is torn, improperly lapped, or installed without taped seams at joints and penetrations fails at its primary function — and the failure is invisible until moisture damage in the wall assembly becomes severe enough to present symptoms on the interior or exterior surface.
In Apex's climate — 48 inches of average annual rainfall, summer relative humidity regularly above 70%, and freeze-thaw cycles each winter — the weather-resistive barrier is the wall assembly's first and most critical line of defense against moisture intrusion. The U.S. Department of Energy estimates that air leakage through gaps in the building envelope accounts for 25–40% of heating and cooling energy loss in a typical home. A correctly installed, fully taped house wrap with integrated flashing at all openings addresses both moisture protection and air infiltration simultaneously. Apex Pro Siding & Wrap installs weather-resistive barrier systems on new construction and re-siding projects throughout Wake and Chatham counties.
Why Choose Us
Local Siding Contractors with Actual Experience
We have completed thousands of residential and commercial siding projects across Apex, Cary, Holly Springs, Morrisville, Fuquay-Varina, Raleigh, Wake Forest, Chapel Hill, Durham, and Pittsboro. We understand the housing stock in this area specifically.
Advanced Installation & Repair Methods
Our installation teams are trained on full water-managed wall assembly techniques: continuous house wrap with taped seams, integrated kick-out flashing at all roof-wall intersections, foam backer rod and sealant at all penetrations, and proper clearances between siding and grade or roofing.
Proven Track Record
Thousands of completed projects in the Research Triangle region span single-family residential re-siding, new construction builds, commercial retail and office exteriors, and multi-family properties. More than 94% of our residential customers in the past three years came from referrals or repeat business, which reflects project outcomes more accurately than any other metric.
Get a FREE On-Site Estimate
Some of the Products We Proudly Use
House Wrap & Vapor Barrier Installation Services We Provide
Existing WRB Assessment and Removal
On re-siding projects, we assess the condition of the existing weather-resistive barrier after removing the old siding before making any recommendation about whether it can be retained or must be replaced. A house wrap that has been in service for 20 or more years may have degraded to the point where its permeability and tensile strength no longer meet code requirements. We check for tears, failed tape at seams and penetrations, improper lapping that allows water to run behind rather than over the WRB, and areas where the barrier has been cut for utilities and never properly resealed. Our recommendation — retain or replace — is provided in writing with photographic documentation of the existing condition.
Tyvek HomeWrap Installation
DuPont Tyvek HomeWrap is the most widely specified house wrap product in U.S. residential construction and has a 40-year track record in the Southeast's humid climate. We install Tyvek with a minimum 6-inch horizontal overlap between courses, lapped shingle-style so upper courses overlap lower courses and water cannot run behind the seam. All vertical seams, horizontal laps, and penetrations are taped with Tyvek Tape or DuPont FlexWrap NF at window and door openings. Tyvek is fastened with cap nails or staples at maximum 18-inch spacing to prevent billowing or displacement before siding installation.
ZIP System Sheathing Installation
ZIP System by Huber Engineered Woods integrates the structural sheathing panel and the weather-resistive barrier into a single product — a structural panel with a factory-applied water-resistive barrier on the face. ZIP System eliminates the separate house wrap installation step, reduces labor time, and produces a more consistently airtight assembly than field-applied house wrap because the barrier is bonded to the panel rather than mechanically fastened over it. All ZIP System panel seams are taped with ZIP System Tape, and all window and door openings are flashed with ZIP System Stretch Tape before window installation. ZIP System is our default recommendation for new construction projects and full re-sheathing scenarios on re-siding projects.
Window and Door Flashing Integration
The majority of moisture intrusion events in residential wall assemblies originate at window and door openings — not through the field of the house wrap. Correct flashing sequence at rough openings is sill pan flashing first, then house wrap lapped over the sill pan, then jamb flashing lapped over the house wrap at the sides, then head flashing lapped over the jamb flashing at the top. This shingle-lapped sequence ensures water that enters behind the window casing drains out at the sill rather than into the wall cavity. We install DuPont FlexWrap NF at sill pans — a flexible, self-adhering membrane that conforms to the rough opening corners where flat tape cannot maintain adhesion.
Kick-Out Flashing and Roof-Wall Integration
Kick-out flashing at roof-wall intersections is one of the most commonly omitted details in residential construction and one of the highest-risk moisture intrusion points in a wall assembly. Where a sloped roof meets a vertical wall, water running down the roof surface will follow the step flashing into the wall cavity unless a kick-out diverter redirects it away from the wall. We install code-compliant kick-out flashing at every roof-wall intersection on every project — new construction and re-siding alike — using metal kick-out diverters integrated with the step flashing and counter flashing sequence.
Penetration Sealing and Air Barrier Continuity
Utility penetrations through the wall assembly — electrical, plumbing, HVAC, and communication conduits — are common air and moisture leakage points that are frequently left unsealed or sealed with materials that fail within five years. We seal all penetrations through the weather-resistive barrier with foam backer rod and an exterior-rated sealant compatible with the WRB material. On ZIP System installations, all penetrations receive ZIP System Tape wrapped around the conduit and adhered to the panel face to maintain air barrier continuity. Air barrier continuity at penetrations is a requirement of the NC Energy Conservation Code for new construction and significantly affects blower door test results.
Types of Properties We Serve
New Residential Construction
New construction is the most straightforward application for house wrap and WRB system installation — the wall assembly is open, framing is accessible, and the WRB can be installed in the correct sequence relative to windows, doors, and roofing. We work with residential builders throughout Wake and Chatham counties on new construction WRB packages, coordinating with framing and window installation schedules to maintain the correct installation sequence. All new construction WRB installations are inspected by the Town of Apex Inspections Department or applicable jurisdiction as part of the framing and sheathing inspection.
Re-Siding Projects
Re-siding is the most common scenario for WRB replacement in the existing housing stock. When siding is removed for replacement, the existing WRB is exposed and can be assessed for condition. In Apex's 1990s and 2000s-era housing stock — where original house wrap may be 20–30 years old and was frequently installed without taped seams under the standards of that era — WRB replacement at the time of re-siding is often the right call. We assess every re-siding project for WRB condition and provide a written recommendation before finalizing the project scope.
Commercial Construction
Commercial wall assemblies in North Carolina require a continuous air barrier in addition to a weather-resistive barrier under the NC Energy Conservation Code for commercial buildings. We install commercial WRB and air barrier systems including Tyvek CommercialWrap, Henry Blueskin VP100, and ZIP System on commercial construction projects, coordinating with general contractors on sequencing and inspection scheduling. Commercial air barrier installations are tested for continuity as part of building envelope commissioning on applicable project types.
Existing Homes with Active Moisture Problems
Homeowners experiencing interior moisture symptoms — wall staining, mold, peeling interior paint at exterior walls — frequently have a failed or improperly installed WRB as the root cause. We assess these situations by removing siding in the affected area, evaluating the WRB and substrate condition, and providing a written diagnosis with repair scope. Addressing an active moisture intrusion problem requires correcting the WRB failure, not just treating the interior symptoms.
What Our Customers are Saying
"We did a full re-side and Apex Pro recommended replacing the original house wrap after showing us photographs of the failed tape at every window opening. Seeing the condition of what was behind our siding made the decision easy. The new ZIP System installation is night and day."
— Tom and Rachel B., Apex, NC
"Our new construction builder used Apex Pro for the full WRB package. The framing inspection passed on the first visit and the building inspector specifically commented on the flashing quality at the window openings."
— Mark and Jennifer S., Holly Springs, NC
"We had persistent moisture staining on an interior wall for three years. Two contractors told us it was a roof issue. Apex Pro opened the wall, found a failed sill pan flashing at the window above, and fixed the actual problem. No more staining after two full rain seasons."
— Diana F., Cary, NC
House Wrap & Vapor Barrier Installation FAQs
What is the difference between house wrap and a vapor barrier, and do I need both?
House wrap is a weather-resistive barrier — it blocks liquid water from entering the wall assembly while remaining vapor-permeable enough to allow moisture vapor to escape outward. A vapor barrier is a low-permeability membrane that blocks vapor movement entirely. In North Carolina's mixed-humid climate, the NC Residential Building Code does not require an interior vapor barrier in most residential wall assemblies — the climate is warm enough that a vapor barrier on the exterior would trap moisture in the wall cavity and cause more damage than it prevents. What the code does require is a weather-resistive barrier on all exterior walls under siding. If you have been told you need a vapor barrier on the outside of your wall assembly in North Carolina, that is incorrect.
How do I know if my existing house wrap needs to be replaced during a re-side?
The indicators we look for during a re-siding assessment are: tears or holes in the WRB field, failed or missing tape at seams and penetrations, improper lapping where upper courses run under lower courses rather than over them, degradation of the WRB material to the point where it tears easily when probed, and evidence of moisture staining on the sheathing behind the WRB. House wrap installed in the 1990s and early 2000s was frequently installed without taped seams — a standard that has since been superseded by code and manufacturer requirements. If your home was built before 2005 and has never had its WRB replaced, replacement at the time of re-siding is very likely the right call.
Does ZIP System replace house wrap entirely?
Yes. ZIP System integrates the structural sheathing and the weather-resistive barrier into a single panel. When ZIP System panels are installed with all seams taped using ZIP System Tape and all openings flashed with ZIP System Stretch Tape, a separate house wrap is not required and is not installed. ZIP System produces a more consistently airtight assembly than field-applied house wrap because the barrier is factory-bonded to the panel rather than mechanically fastened over it — eliminating the risk of gaps between the WRB and sheathing that reduce air barrier performance.
Can house wrap be repaired rather than replaced on a re-siding project?
Minor tears and isolated penetration failures in an otherwise sound WRB can be repaired with compatible tape products — Tyvek Tape on Tyvek installations, ZIP System Tape on ZIP panels. Widespread seam failures, large tears, or a WRB that has been in service for 25 or more years are not candidates for repair — the material's tensile strength and permeability characteristics degrade over time, and patching a compromised barrier does not restore its full performance. We assess each situation individually and do not recommend replacement when repair is genuinely sufficient.
Is house wrap installation included in a full siding replacement project?
It depends on the condition of the existing WRB. On every re-siding project, we assess the WRB after removing the existing siding and provide a written recommendation. If the existing WRB is in good condition — intact, properly lapped, taped seams, no moisture staining on the sheathing — we will tell you it can be retained and we will repair any isolated failures before new siding goes on. If replacement is warranted, WRB replacement is added to the project scope with a separate line item in the contract so the cost is transparent before work proceeds.