Plan HG-2668•Duplex / Multi-Gen•70' × 40' Footprint

2,800 Sq Ft (40x70) 3 Bed 2 Bath Duplex / Multi-Gen Floor Plan (STC-60 Mirrored Acoustic Party-Wall Duplex)

2,800 sq ft heated living • 3 Bedrooms, 2 Baths • Free 2D CAD Blueprint (.SVG)

Download Free CAD (.SVG)

Room Dimensions & Zones

70' × 40' Shell

UNIT A SUITE

387 sq ft

21'-6" × 18'-0"

UNIT A BATH

243 sq ft

13'-6" × 18'-0"

UNIT A LIVING

473 sq ft

21'-6" × 22'-0"

UNIT A KITCHEN

297 sq ft

13'-6" × 22'-0"

UNIT B BATH

243 sq ft

13'-6" × 18'-0"

UNIT B SUITE

387 sq ft

21'-6" × 18'-0"

UNIT B KITCHEN

297 sq ft

13'-6" × 22'-0"

UNIT B LIVING

473 sq ft

21'-6" × 22'-0"

Build Cost Estimator

Estimated Cost to Build (70' × 40' Duplex / Multi-Gen)

Region:

Shell / Building Kit

$109,000 – $139,500

Framing package, roof trusses & exterior shell for 2,800 sq ft base.

Owner-Builder

$285,500 – $375,500

Saves ~$128,500 by managing local slab & interior trades.

Turnkey Builder

$414,000 – $504,000

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

Est. Monthly Payment

$2,382 / mo

$367,200 financed (30-Yr)

Down Payment:20%

Interest Rate:6.75%

Free Vector CAD Blueprint • Plan HG-2668

Download 70' × 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 (47 yd³), roof surface (~3,397 sq ft), wall framing & architectural notes

Building Package	Specification	Quantity	Est. Range
Structural Shell & Trusses	70'×40' 2x6 Exterior + Double-Stud Insulated Acoustic Party Wall	2,800 sq ft shell kit	$109,000 – $139,500
Concrete Slab & Grade Beams	Monolithic Concrete Slab w/ Dual Sewer/Water Stub-Outs	47 Cubic Yards (4,000 PSI)	$27,500 – $35,000
Roofing & Underlayment	Architectural Shingle or Standing Seam Metal Hip/Gable (5:12 Pitch)	38 Roofing Squares (3,800 sq ft)	$15,960 – $25,840
Closed-Cell Spray Foam / Insulation	3" Closed-Cell Wall & Roof Deck Thermal Envelope (R-21 to R-38)	15,930 Board Feet	$21,506 – $29,471
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	5.5 Ton (66,000 BTU/hr)	$14,300 – $22,550

Exterior Perimeter

220 Linear Ft

Interior Partitions

~216 Linear Ft

Est. Concrete Slab

47 Cubic Yards

Roof Deck Area

~3,397 Sq Ft

Plan HG-2668 (2,800 Sq Ft (40x70) 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 70'-0" × 40'-0" structural grid (2,800 sq ft base footprint, 0.57:1 Square-Bay Proportion). Configured on the STC-60 Mirrored Acoustic Party-Wall Duplex topology, this layout delivers 2,800 sq ft of conditioned residential living area and 420 sq ft of covered outdoor porch deck.

Inside the conditioned envelope, the floor plan is organized into 8 distinct architectural zones: UNIT A SUITE (21'-6" × 18'-0", 387 sq ft), UNIT A BATH (13'-6" × 18'-0", 243 sq ft), UNIT A LIVING (21'-6" × 22'-0", 473 sq ft), UNIT A KITCHEN (13'-6" × 22'-0", 297 sq ft), UNIT B BATH (13'-6" × 18'-0", 243 sq ft), UNIT B SUITE (21'-6" × 18'-0", 387 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 387 sq ft; UNIT B SUITE at 387 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 70' clear-span width utilizes 2x6 exterior + double-stud insulated acoustic party wall bearing on 220 linear feet of 6" exterior wall framing (~227 framing studs/posts) and 216 linear feet of interior partitions. The 5:12 architectural shingle or standing seam metal hip/gable requires approximately 3,397 sq ft of roofing material (38 roofing squares), while the monolithic concrete slab w/ dual sewer/water stub-outs pours at an estimated 47 cubic yards of 4,000-PSI concrete.

Frequently Asked Questions • Plan HG-2668

Building costs, foundation specs, egress & CAD customization questions

How much does it cost to build the 70x40 2,800 Sq Ft (40x70) 3 Bed 2 Bath Duplex / Multi-Gen Floor Plan (STC-60 Mirrored Acoustic Party-Wall Duplex) (HG-2668)?

Based on current national residential construction data for duplex / multi-gen structures, the dried-in structural shell for Plan HG-2668 (2,800 sq ft base footprint) ranges from $109,000 to $139,500 ($40/sq ft baseline). A complete turnkey build—including the 47-yard concrete foundation, 216 linear feet of interior framing, MEP rough-ins for 2 bath(s), and interior finishes across 2,800 sq ft of heated space—ranges from $414,000 to $504,000. 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 2,800 sq ft 3-bedroom layout?

Plan HG-2668 features 8 architecturally solved spaces inside its 70' × 40' footprint: UNIT A SUITE (21'-6" × 18'-0", 387 sq ft), UNIT A BATH (13'-6" × 18'-0", 243 sq ft), UNIT A LIVING (21'-6" × 22'-0", 473 sq ft), UNIT A KITCHEN (13'-6" × 22'-0", 297 sq ft), UNIT B BATH (13'-6" × 18'-0", 243 sq ft), UNIT B SUITE (21'-6" × 18'-0", 387 sq ft), UNIT B KITCHEN (13'-6" × 22'-0", 297 sq ft), UNIT B LIVING (21'-6" × 22'-0", 473 sq ft). Every habitable room meets or exceeds IRC R304 minimum area (70+ sq ft) and minimum horizontal dimension (7'-0"+) requirements.

Can this 70' × 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 70'-0" × 40'-0" structural grid (220 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-2668?

Downloading Plan HG-2668 provides the high-resolution scalable vector floor plan (.SVG) with crisp architectural lineweights, exterior dimension strings (70'-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.