Plan HG-2688•Duplex / Multi-Gen•80' × 40' Footprint

3,200 Sq Ft (40x80) 3 Bed 2 Bath Duplex / Multi-Gen Floor Plan (STC-60 Mirrored Acoustic Party-Wall Duplex)

3,200 sq ft heated living • 3 Bedrooms, 2 Baths • Free 2D CAD Blueprint (.SVG)

Download Free CAD (.SVG)

Room Dimensions & Zones

80' × 40' Shell

UNIT A SUITE

450 sq ft

25'-0" × 18'-0"

UNIT A BATH

270 sq ft

15'-0" × 18'-0"

UNIT A LIVING

550 sq ft

25'-0" × 22'-0"

UNIT A KITCHEN

330 sq ft

15'-0" × 22'-0"

UNIT B BATH

270 sq ft

15'-0" × 18'-0"

UNIT B SUITE

450 sq ft

25'-0" × 18'-0"

UNIT B KITCHEN

330 sq ft

15'-0" × 22'-0"

UNIT B LIVING

550 sq ft

25'-0" × 22'-0"

Build Cost Estimator

Estimated Cost to Build (80' × 40' Duplex / Multi-Gen)

Region:

Shell / Building Kit

$124,500 – $159,500

Framing package, roof trusses & exterior shell for 3,200 sq ft base.

Owner-Builder

$326,000 – $429,000

Saves ~$147,000 by managing local slab & interior trades.

Turnkey Builder

$473,000 – $576,000

Full general contractor finish including slab, HVAC, kitchen & baths.

Est. Monthly Payment

$2,722 / mo

$419,600 financed (30-Yr)

Down Payment:20%

Interest Rate:6.75%

Free Vector CAD Blueprint • Plan HG-2688

Download 80' × 40' Duplex / Multi-Gen Floor Plan (.SVG)

Scalable 2D architectural vector drawing with exterior and room dimensions, door swings, and fixture layout. Opens in AutoCAD, Illustrator, Inkscape, or any browser.

Material Takeoff & Framing Specifications

Concrete volume (53 yd³), roof surface (~3,883 sq ft), wall framing & architectural notes

Building Package	Specification	Quantity	Est. Range
Structural Shell & Trusses	80'×40' 2x6 Exterior + Double-Stud Insulated Acoustic Party Wall	3,200 sq ft shell kit	$124,500 – $159,500
Concrete Slab & Grade Beams	Monolithic Concrete Slab w/ Dual Sewer/Water Stub-Outs	53 Cubic Yards (4,000 PSI)	$31,500 – $40,000
Roofing & Underlayment	Architectural Shingle or Standing Seam Metal Hip/Gable (5:12 Pitch)	44 Roofing Squares (4,400 sq ft)	$18,480 – $29,920
Closed-Cell Spray Foam / Insulation	3" Closed-Cell Wall & Roof Deck Thermal Envelope (R-21 to R-38)	17,880 Board Feet	$24,138 – $33,078
Windows & Exterior Doors	Low-E Argon Black Architectural Glazing + 36" Fiberglass Entry	4 Windows • 6 Doors	$3,800 – $6,020
HVAC & Multi-Zone Mini-Split	High-SEER2 Heat Pump / Ductless Mini-Split System	6.5 Ton (78,000 BTU/hr)	$16,900 – $26,650

Exterior Perimeter

240 Linear Ft

Interior Partitions

~230 Linear Ft

Est. Concrete Slab

53 Cubic Yards

Roof Deck Area

~3,883 Sq Ft

Plan HG-2688 (3,200 Sq Ft (40x80) 3 Bed 2 Bath Duplex / Multi-Gen Floor Plan (STC-60 Mirrored Acoustic Party-Wall Duplex)) is an IRC R304/R310-vetted duplex / multi-gen blueprint engineered around a 80'-0" × 40'-0" structural grid (3,200 sq ft base footprint, 0.5:1 Square-Bay Proportion). Configured on the STC-60 Mirrored Acoustic Party-Wall Duplex topology, this layout delivers 3,200 sq ft of conditioned residential living area and 480 sq ft of covered outdoor porch deck.

Inside the conditioned envelope, the floor plan is organized into 8 distinct architectural zones: UNIT A SUITE (25'-0" × 18'-0", 450 sq ft), UNIT A BATH (15'-0" × 18'-0", 270 sq ft), UNIT A LIVING (25'-0" × 22'-0", 550 sq ft), UNIT A KITCHEN (15'-0" × 22'-0", 330 sq ft), UNIT B BATH (15'-0" × 18'-0", 270 sq ft), UNIT B SUITE (25'-0" × 18'-0", 450 sq ft). Plumbing rough-ins are consolidated across UNIT A BATH, UNIT A KITCHEN, UNIT B BATH, UNIT B KITCHEN to minimize sub-slab trenching and manifold pipe runs. Sleeping quarters (UNIT A SUITE at 450 sq ft; UNIT B SUITE at 450 sq ft) are acoustically buffered from the primary living core and positioned on exterior elevations for code-compliant egress glazing.

From a builder takeoff standpoint, the 80' clear-span width utilizes 2x6 exterior + double-stud insulated acoustic party wall bearing on 240 linear feet of 6" exterior wall framing (~244 framing studs/posts) and 230 linear feet of interior partitions. The 5:12 architectural shingle or standing seam metal hip/gable requires approximately 3,883 sq ft of roofing material (44 roofing squares), while the monolithic concrete slab w/ dual sewer/water stub-outs pours at an estimated 53 cubic yards of 4,000-PSI concrete.

Frequently Asked Questions • Plan HG-2688

Building costs, foundation specs, egress & CAD customization questions

How much does it cost to build the 80x40 3,200 Sq Ft (40x80) 3 Bed 2 Bath Duplex / Multi-Gen Floor Plan (STC-60 Mirrored Acoustic Party-Wall Duplex) (HG-2688)?

Based on current national residential construction data for duplex / multi-gen structures, the dried-in structural shell for Plan HG-2688 (3,200 sq ft base footprint) ranges from $124,500 to $159,500 ($40/sq ft baseline). A complete turnkey build—including the 53-yard concrete foundation, 230 linear feet of interior framing, MEP rough-ins for 2 bath(s), and interior finishes across 3,200 sq ft of heated space—ranges from $473,000 to $576,000. Use the interactive Regional Cost Multiplier on this page to adjust for your local labor market and owner-builder sweat equity.

What are the exact room dimensions inside this 3,200 sq ft 3-bedroom layout?

Plan HG-2688 features 8 architecturally solved spaces inside its 80' × 40' footprint: UNIT A SUITE (25'-0" × 18'-0", 450 sq ft), UNIT A BATH (15'-0" × 18'-0", 270 sq ft), UNIT A LIVING (25'-0" × 22'-0", 550 sq ft), UNIT A KITCHEN (15'-0" × 22'-0", 330 sq ft), UNIT B BATH (15'-0" × 18'-0", 270 sq ft), UNIT B SUITE (25'-0" × 18'-0", 450 sq ft), UNIT B KITCHEN (15'-0" × 22'-0", 330 sq ft), UNIT B LIVING (25'-0" × 22'-0", 550 sq ft). Every habitable room meets or exceeds IRC R304 minimum area (70+ sq ft) and minimum horizontal dimension (7'-0"+) requirements.

Can this 80' × 40' floor plan be built with post-frame, red-iron steel, or 2x6 stick framing?

Yes. Because the outer envelope is engineered on an even 80'-0" × 40'-0" structural grid (240 LF perimeter) with clear-span 5:12 trusses, a local structural engineer or building kit supplier can adapt the blueprint for 2x6 Exterior + Double-Stud Insulated Acoustic Party Wall, conventional 2x6 stick framing at 16" o.c., laminated post-frame columns at 8' o.c., or structural insulated panels (SIPs).

What files are included in the free CAD blueprint download for Plan HG-2688?

Downloading Plan HG-2688 provides the high-resolution scalable vector floor plan (.SVG) with crisp architectural lineweights, exterior dimension strings (80'-0" × 40'-0"), room-by-room callouts, door swing arcs, and window schedules, plus instant browser printing for contractor bidding and preliminary municipal zoning review.