Beginner

House plans: design with Sweet Home 3D or SketchUp

10 min read

Drawing your own house plans is tempting — and perfectly achievable for straightforward projects. Free software like Sweet Home 3D and SketchUp lets you move from a house brief to a concrete plan, complete with 3D view, with no technical drawing skills required. But a word of caution: software is no substitute for an architect — there are limits you need to know before you start.

SWEET HOME 3D vs SKETCHUP: COMPARISON SWEET HOME 3D Free, open source Learning curve 1-2h Dimensioned 2D plan ✓ Real-time 3D view ✓ Furniture catalogue 1400+ Sloping site ✗ Complex roof ✗ Realistic render ✗ DWG/PDF export PDF Ideal for 90% of projects SKETCHUP Free (web) / ~£250/year Learning curve 5-10h Dimensioned 2D plan Plugin Real-time 3D view ✓ Furniture catalogue 3D Warehouse Sloping site ✓ Complex roof ✓ Realistic render ✓ DWG/PDF export DWG (Pro) For complex projects Both are free — start with Sweet Home 3D, move to SketchUp if needed

Sweet Home 3D: the best choice for beginners

Why Sweet Home 3D?

Sweet Home 3D is a free, open-source application available on Windows, Mac and Linux. It is designed specifically for drawing house plans, even with no prior experience.

Feature Detail
Price Free (full version)
Learning curve 1–2 hours to get started
2D + 3D view Simultaneous, in real time
Furniture catalogue 1,400+ objects (furniture, sanitary ware, appliances)
Dimensions Automatic on the plan
Export PDF, image, 3D walkthrough video
Limitations No structural calculations, no technical section drawings

How to draw your plan in 5 steps

Step 1: Draw the walls

Use the “Create walls” tool to trace the outline of your house. Set the thickness to 20 cm for block/masonry load-bearing walls or 18 cm for a timber frame.

Tip — Start with the external perimeter, then add the internal walls. Use the magnetic grid (10 cm increments) to keep everything aligned. Dimensions are displayed automatically as you draw.

Step 2: Place openings

Drag doors and windows from the catalogue. Sweet Home 3D inserts them into the walls automatically and creates the openings.

  • Internal doors: 83 cm wide as standard, 93 cm for wheelchair accessibility.
  • Front door: 90 cm minimum.
  • Windows: match the size to the solar orientation. Large glazing to the south, smaller windows to the north.

Step 3: Define the rooms

Name each room and assign a floor colour. Sweet Home 3D automatically calculates the area of each room — compare with your house brief to check that the areas match.

Step 4: Furnish in 3D

Place furniture to verify that the dimensions are realistic:

  • Kitchen: check the activity triangle (fridge–sink–hob) with a minimum 120 cm circulation zone.
  • Bedrooms: a 140×190 bed + a wardrobe + 60 cm clearance on each side.
  • Bathroom: 90×90 shower minimum, WC with 60 cm clearance in front.

Step 5: Check in 3D

Switch to the 3D view and “walk through” your house virtually. This is where you spot the problems: a room that is too narrow, a door opening the wrong way, an unnecessary corridor.

Good practice — Take the whole family on a virtual tour of the 3D plan. Everyone should be able to picture themselves in the rooms they will use. It is far more effective than a flat 2D plan.

SketchUp: going further

When to choose SketchUp over Sweet Home 3D?

SketchUp is a general-purpose 3D modelling tool — more powerful than Sweet Home 3D, but with a steeper learning curve.

Feature Sweet Home 3D SketchUp Free
Price Free Free (web) / ~£250/year (desktop)
Learning 1–2h 5–10h
2D plan Native Plugin/extension
3D modelling Basic Advanced (freeform shapes)
Roof Simple (gable, hip) Complex (mansard, flat, split-level)
Sloping site No Yes (terrain modelling)
Realistic render No Yes (with V-Ray or Enscape)
Community Small Huge (3D Warehouse)

Question

When to use SketchUp?

  • You want to model a sloping site and see how the house sits within it.
  • You have a complex roof (mansard, flat roof, split levels).
  • You want to produce realistic renders to visualise materials and colours.
  • You plan to hand a 3D model to your architect as a starting point.

Tip — The free web version of SketchUp (app.sketchup.com) is sufficient for a pre-application design. There is no need to purchase the Pro version unless you need to export in DWG format for an architect.

Other software worth knowing

Software Type Price Best for
Kozikaza Web, plan + 3D Free Beginners, quick results
HomeByMe Web, plan + 3D Free (limited) Beginners, attractive renders
Archifacile Desktop, 2D plan ~£70 Simple dimensioned plans
Autodesk Revit Pro, BIM ~£2,500/year Architects, engineers
ArchiCAD Pro, BIM ~£4,000/year Architects

For a self-builder, Sweet Home 3D covers 90% of needs. SketchUp handles the remaining 10% (complex site, realistic render).

Design rules to follow

Drawing a plan is not just about placing walls. Here are the key rules:

Minimum dimensions

Element Minimum Comfortable
Corridor width 90 cm 110 cm
Standard door width 83 cm 93 cm (accessible)
Ceiling height 2.50 m 2.60–2.70 m
Legal bedroom area 9 m² 12 m²+
Clearance in front of WC 60 cm 80 cm
Kitchen worktop clearance 90 cm 120 cm

Common mistakes

  1. Forgetting wall thickness — A rendered block wall is 23 cm thick. If you draw 10 cm walls, your plan will be larger on paper but unrealistic in reality.

  2. Doors clashing — Check that doors do not bang into each other when open. Draw the door swing arc.

  3. Corridors that are too long — More than 15% of the floor area in circulation space = a poorly optimised plan. Revisit our article on circulation.

  4. Forgetting storage — Allow a built-in wardrobe per bedroom, a utility room, and an entrance with storage.

  5. Poorly oriented windows — Large glazing to the south for passive solar gain, small openings to the north.

Conseil

From amateur plan to planning permission

Warning — A plan made in Sweet Home 3D or SketchUp is not sufficient for planning permission. A planning application requires standardised drawings: location plan, site plan, section drawing, dimensioned elevations (planning drawings). These must be produced by an architectural technician / draughtsman or an architect.

But your amateur plan is an excellent starting point:

  1. You design the plan with Sweet Home 3D → brief, areas, circulation.
  2. You validate the 3D plan with your family → adjustments, modifications.
  3. You hand over the plan to a draughtsman → they redraw it to the required standards for the planning application.
  4. You save 50% of the draughtsman’s time → they start from your base, not from scratch.
flowchart TD A[House brief defined] --> B[Plan in Sweet Home 3D] B --> C{Floor area > 150 m2?} C -->|Yes| D[Architect required] C -->|No| E{Complex design?} E -->|Yes| F[Draughtsman or architect] E -->|No| G[Draughtsman alone sufficient] D --> H[Planning drawings to standard] F --> H G --> H style A fill:#0F4C81,stroke:#0F4C81,color:#fff style B fill:#F58220,stroke:#F58220,color:#fff style C fill:#FDFCF9,stroke:#C67A3C,color:#0F4C81 style E fill:#FDFCF9,stroke:#C67A3C,color:#0F4C81 style D fill:#CD212A,stroke:#CD212A,color:#fff style F fill:#F58220,stroke:#F58220,color:#fff style G fill:#56C6A9,stroke:#56C6A9,color:#fff style H fill:#56C6A9,stroke:#56C6A9,color:#fff

Key takeaways

Sweet Home 3D is the ideal tool for designing your first house plan. It is free, intuitive and sufficient for 90% of projects at the pre-application stage. But do not forget: it is a design tool, not a production tool. Planning permission requires professional drawings — your Sweet Home 3D plan will serve as the brief for your draughtsman or architect.

Checklist: designing your plans

  • House brief written (rooms, areas, circulation)
  • Software chosen (Sweet Home 3D for most projects)
  • External perimeter drawn (realistic wall thickness)
  • Internal walls placed (load-bearing and partition walls)
  • Openings positioned (solar orientation respected)
  • Rooms named and areas verified
  • Furniture placed (circulation checked)
  • 3D walkthrough done with the family
  • Minimum dimensions respected (corridors, doors, ceiling heights)
  • Plan handed to a draughtsman or architect for the planning application