diff --git a/Tools/msi/buildrelease.bat b/Tools/msi/buildrelease.bat
index 7f9a81b..5dc1b57 100644
--- a/Tools/msi/buildrelease.bat
+++ b/Tools/msi/buildrelease.bat
@@ -29,6 +29,7 @@
 
 set D=%~dp0
 set PCBUILD=%D%..\..\PCBuild\
+if "%Py_OutDir%"=="" set Py_OutDir=%PCBUILD%
 set EXTERNALS=%D%..\..\externals\windows-installer\
 
 set BUILDX86=
@@ -110,12 +111,12 @@
 
 if "%1" EQU "x86" (
     set PGO=
-    set BUILD=%PCBUILD%win32\
+    set BUILD=%Py_OutDir%win32\
     set BUILD_PLAT=Win32
     set OUTDIR_PLAT=win32
     set OBJDIR_PLAT=x86
 ) else (
-    set BUILD=%PCBUILD%amd64\
+    set BUILD=%Py_OutDir%amd64\
     set PGO=%~2
     set BUILD_PLAT=x64
     set OUTDIR_PLAT=amd64
@@ -167,7 +168,7 @@
 if "%OUTDIR_PLAT%" EQU "win32" (
     %MSBUILD% "%D%launcher\launcher.wixproj" /p:Platform=x86 %CERTOPTS% /p:ReleaseUri=%RELEASE_URI%
     if errorlevel 1 exit /B
-) else if not exist "%PCBUILD%win32\en-us\launcher.msi" (
+) else if not exist "%Py_OutDir%win32\en-us\launcher.msi" (
     %MSBUILD% "%D%launcher\launcher.wixproj" /p:Platform=x86 %CERTOPTS% /p:ReleaseUri=%RELEASE_URI%
     if errorlevel 1 exit /B
 )
diff --git a/Tools/msi/make_zip.proj b/Tools/msi/make_zip.proj
index b3588b7..2141117 100644
--- a/Tools/msi/make_zip.proj
+++ b/Tools/msi/make_zip.proj
@@ -16,8 +16,9 @@
         <TargetPath>$(OutputPath)\$(TargetName)$(TargetExt)</TargetPath>
         <CleanCommand>rmdir /q/s "$(IntermediateOutputPath)\zip_$(ArchName)"</CleanCommand>
         <Arguments>"$(PythonExe)" "$(MSBuildThisFileDirectory)\make_zip.py"</Arguments>
-        <Arguments>$(Arguments) -e -o "$(TargetPath)" -t "$(IntermediateOutputPath)\zip_$(ArchName)" -a $(ArchName)</Arguments>
+        <Arguments>$(Arguments) -e -o "$(TargetPath)" -t "$(IntermediateOutputPath)\zip_$(ArchName)" -b "$(BuildPath.TrimEnd(`\`))"</Arguments>
         <Environment>set DOC_FILENAME=python$(PythonVersion).chm</Environment>
+        <Environment>$(Environment)%0D%0Aset PYTHONPATH=$(PySourcePath)Lib</Environment>
         <Environment Condition="Exists($(CRTRedist))">$(Environment)%0D%0Aset VCREDIST_PATH=$(CRTRedist)\$(Platform)</Environment>
     </PropertyGroup>
 
diff --git a/Tools/msi/make_zip.py b/Tools/msi/make_zip.py
index 0034f6b..8e35bdc 100644
--- a/Tools/msi/make_zip.py
+++ b/Tools/msi/make_zip.py
@@ -106,23 +106,23 @@
 BASE_NAME = 'python{0.major}{0.minor}'.format(sys.version_info)
 
 FULL_LAYOUT = [
-    ('/', 'PCBuild/$arch', 'python.exe', is_not_debug),
-    ('/', 'PCBuild/$arch', 'pythonw.exe', is_not_debug),
-    ('/', 'PCBuild/$arch', 'python{}.dll'.format(sys.version_info.major), is_not_debug),
-    ('/', 'PCBuild/$arch', '{}.dll'.format(BASE_NAME), is_not_debug),
-    ('DLLs/', 'PCBuild/$arch', '*.pyd', is_not_debug),
-    ('DLLs/', 'PCBuild/$arch', '*.dll', is_not_debug_or_python),
+    ('/', '$build', 'python.exe', is_not_debug),
+    ('/', '$build', 'pythonw.exe', is_not_debug),
+    ('/', '$build', 'python{}.dll'.format(sys.version_info.major), is_not_debug),
+    ('/', '$build', '{}.dll'.format(BASE_NAME), is_not_debug),
+    ('DLLs/', '$build', '*.pyd', is_not_debug),
+    ('DLLs/', '$build', '*.dll', is_not_debug_or_python),
     ('include/', 'include', '*.h', None),
     ('include/', 'PC', 'pyconfig.h', None),
     ('Lib/', 'Lib', '**/*', include_in_lib),
-    ('libs/', 'PCBuild/$arch', '*.lib', include_in_libs),
+    ('libs/', '$build', '*.lib', include_in_libs),
     ('Tools/', 'Tools', '**/*', include_in_tools),
 ]
 
 EMBED_LAYOUT = [
-    ('/', 'PCBuild/$arch', 'python*.exe', is_not_debug),
-    ('/', 'PCBuild/$arch', '*.pyd', is_not_debug),
-    ('/', 'PCBuild/$arch', '*.dll', is_not_debug),
+    ('/', '$build', 'python*.exe', is_not_debug),
+    ('/', '$build', '*.pyd', is_not_debug),
+    ('/', '$build', '*.dll', is_not_debug),
     ('{}.zip'.format(BASE_NAME), 'Lib', '**/*', include_in_embeddable_lib),
 ]
 
@@ -187,15 +187,15 @@
     parser.add_argument('-o', '--out', metavar='file', help='The name of the output archive', type=Path, default=None)
     parser.add_argument('-t', '--temp', metavar='dir', help='A directory to temporarily extract files into', type=Path, default=None)
     parser.add_argument('-e', '--embed', help='Create an embedding layout', action='store_true', default=False)
-    parser.add_argument('-a', '--arch', help='Specify the architecture to use (win32/amd64)', type=str, default="win32")
+    parser.add_argument('-b', '--build', help='Specify the build directory', type=Path, default=None)
     ns = parser.parse_args()
 
     source = ns.source or (Path(__file__).resolve().parent.parent.parent)
     out = ns.out
-    arch = ns.arch
+    build = ns.build or Path(sys.exec_prefix)
     assert isinstance(source, Path)
     assert not out or isinstance(out, Path)
-    assert isinstance(arch, str)
+    assert isinstance(build, Path)
 
     if ns.temp:
         temp = ns.temp
@@ -218,7 +218,10 @@
 
     try:
         for t, s, p, c in layout:
-            fs = source / s.replace("$arch", arch)
+            if s == '$build':
+                fs = build
+            else:
+                fs = source / s
             files = rglob(fs, p, c)
             extra_files = []
             if s == 'Lib' and p == '**/*':