In this tutorial you`ll learn how to create simple house using polygon modeling , create UV map, and texture it.
Start by creating a polygon box. Add edge loop as shown on picture.

Select highlighted face and extrude it along z axis.


Using cut faces tool (polygons>edit mesh/cut faces tool) cut top faces as shown on picture.

Select highlighted faces and move them along y axis to create roof.

You should get result similar to picture below

This completes modeling part. Before creating UV map, create texture using photoshop or other image editing software. Here is example for texture:

Open hypershade editor and create lambert material. For color set file and choose texture you created. Assign material to object.
Select face shown on picture. To create UV for this face we will use planar projection because this face is basically a plane. To do this go to polygons>create UVs/planar mapping and for axis choose z axis, because it is perpendicular to plane. When you do planar mapping its usually best to choose axis that is perpendicular to plane you want to create UV for.
Open UV texture editor. Go to UV selection mode and select UVs you just created, move and scale them to corresponding position on texture.
Here are some tools of UV texture editor explained:

Another useful option is select shell. It can be found under select/select shell of the UV texture editor menu. Select shell selects all UVs connected to selected UV. For example: you select some faces, do the planar mapping, and in UV editor go to UV selection mode, select only one UV point of part you just mapped and click select shell. It will select all UVs related to projection.

Using techniques described earlier , map rest of the faces. Make sure you select axis that is perpendicular to face you`re mapping to get good result.
Here is example of UV mapped object


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